Heating element with coating for aerosol-generating device

Abstract

Disclosed is a heating element for heating an aerosol-forming substrate of an aerosol-generating article received in an aerosol-generating device, the heating element comprising: a heating base element configured to heat the aerosol-forming substrate at least by means of thermal radiation; and a coating material, such as aluminum nitride, disposed on the heating base element. The coating material is configured to increase an amount of thermal radiation absorbed by a first chemical component of the aerosol-forming substrate, such as nicotine, propylene glycol, or glycerol, and to reduce an amount of thermal radiation absorbed by a second chemical component of the aerosol-forming substrate, such as water. The heating element may be an internal heating element of the aerosol-generating device, or may be an external susceptor of the aerosol-generating article.

Description

Technical Field

[0001] This invention relates to a heating element for heating an aerosol-forming matrix of an aerosol-generating article received in an aerosol-generating apparatus. The heating element includes a coating material configured to increase the amount of thermal radiation provided to the aerosol-forming matrix.

[0002] The present invention also relates to a corresponding aerosol generating article comprising such a heating element. Furthermore, the present invention relates to an aerosol generating apparatus and an aerosol generating system. Background Technology

[0003] Aerosol generating devices, particularly electronic nicotine delivery systems (known as ENDS), have become popular worldwide over the past few decades. These devices are alternatives to traditional combustible tobacco products, such as cigarettes.

[0004] Several types of aerosol generating devices are currently available on the market, based on different aerosolization technologies and aerosol generating substrates. A specific subset of aerosol generating devices are heated tobacco products, also known as “heated non-combustible” products and / or systems (HNB). These HNB systems generate inhalable aerosols by heating a tobacco-containing substrate (usually in solid or powder form). Such HNB systems require electronics that include a heating unit to heat the tobacco-containing substrate, rather than burning the tobacco as done in conventional cigarettes.

[0005] Some aerosol generating devices are equipped with a heating chamber or furnace in which an aerosol generating article (or consumable) containing tobacco can be inserted. The tobacco consumable is then heated until an aerosol is formed. The furnace generates a high temperature between approximately 250°C and 400°C, which facilitates the rapid formation of an aerosol that can be inhaled by the user.

[0006] Among aerosol generating devices, there are also liquid-based devices (called e-liquids) in which the liquid is contained in a reservoir. The liquid may or may not contain nicotine to generate an aerosol to be inhaled by the user. These liquid-based aerosol generating devices are convenient for users seeking instant generation of inhalable aerosol. In liquid-based aerosol generating devices, some devices work in conjunction with consumable articles, cartridges, or capsules housed within the device. Consumable articles are typically equipped with a reservoir for the liquid and a heating element. During use, for example, when a user inhales through the device's mouthpiece, the liquid is directed from the reservoir toward the heating element to generate an inhalable aerosol. The heating element can be heated, for example, using a coil. Typically, a wick is applied to deliver the liquid from the reservoir to the heating element.

[0007] All of the above-mentioned aerosol generating devices require heating consumables. There are three main modes of heat transfer: conduction, convection, and radiation. Conduction is the most common and frequently used mode in HNB devices. Convection is rarely used due to its generally low efficiency. Radiative heat transfer is not usually used as the primary mode, but it can occur sometimes, especially when the heating element exhibits a relatively high temperature.

[0008] Radiative heat transfer is emitted and absorbed differently than conductive and / or convective heat transfer because radiation is source- and target-dependent depending on its wavelength. Furthermore, the dominant wavelength emitted by a heat transfer source depends on the material used in the source, its composition, and especially on the coating applied to the source. Additionally, radiation is dependent on thickness and temperature.

[0009] Currently known aerosol generating devices can provide thermal radiation; however, this radiative heat transfer is not optimal. Specifically, heating of specific components in consumables (such as propylene glycol (PG), vegetable glycerin (VG), flavoring agents, nicotine, water, etc.) is not considered. This makes the heating process inefficient. Furthermore, known heating elements (such as sensors) are susceptible to overheating due to their relatively small mass and high power input. This can trigger localized temperature spikes, potentially leading to the burning of the aerosol-forming matrix. Further prior art is known from WO 2021 / 218679 A, ​​CN 112 369 716, EP 4 091 478 A1, and EP 4159 060 A1.

[0010] Therefore, improvements are needed to aerosol generating devices that can provide heat to consumables, especially through radiation.

[0011] Against this backdrop, the object of the present invention is to improve currently known aerosol generating apparatuses. In particular, the object of the present invention is to provide a heating element for heating an aerosol-forming matrix of an aerosol-generating article, which allows for improved radiative heat transfer. This heating element should be more efficient than known heating elements. Furthermore, heat should be provided to the corresponding location where heating is desired. A general objective is to provide a heating element that allows for improved flavor and mouthfeel to be provided to consumers. Summary of the Invention

[0012] The above-mentioned objectives are achieved, at least in part, by the subject matter of the independent claims. Preferred embodiments are the subject matter of the dependent claims, and other suitable aspects of the invention are described through the overall disclosure of this application.

[0013] General aspects

[0014] A first embodiment of the present invention relates to a heating element for heating an aerosol forming matrix of an aerosol generating article received in an aerosol generating apparatus, the heating element comprising: a heating base element configured to heat the aerosol forming matrix at least by means of thermal radiation; and a coating material disposed on the heating base element; wherein the coating material is configured to increase the amount of thermal radiation provided to one or more first components of the aerosol forming matrix compared to the same heating base element without the coating material.

[0015] In this way, the heating element disclosed herein paves the way for improved heat transfer to the aerosol-forming matrix. Specifically, compared to using the same heating base element without a coating, the heating element provides increased heat transfer to one or more first components by means of radiation. The heating element described herein provides more targeted thermal radiation. This reduces overall power consumption and enhances the consumer's inhalation experience. As described in more detail elsewhere herein, the increased amount of thermal radiation can be achieved by means of a shift in the emission spectrum. This shift can be caused by the coating. In particular, the emission spectrum can deviate from the absorption spectrum of water and shift more towards the absorption spectra of nicotine, PG, VG, other wetting agents, and / or aromatic compounds. The latter can be the "first" components as detailed elsewhere herein. The coating material can have the additional advantage of improving the thermal conductivity of the heating base element. The advantage of this can be the mitigation of temperature peaks. This reduces the risk of ablation of components in the aerosol-forming matrix near the heating element.

[0016] Therefore, this disclosure provides an improvement over generally known aerosol generating devices. For example, prior art heating elements do not involve heating specific components via radiation. Furthermore, heating elements (such as sensors) are often subjected to overheating due to temperature peaks. This can lead to matrix burn-off, which is detrimental to consumers as it may result in unpleasant taste, etc.

[0017] It should be noted that the naming of one or more “first” components may imply the provision of additional components (as described in more detail elsewhere in this document). In one example, the heating element may increase the amount of thermal radiation provided only to these first components.

[0018] The heating element used in this disclosure can have any desired shape and can be operated via any heat transfer method. The heating element can be an internal heating element, such as one located near the aerosol-forming matrix and / or integrally formed with the aerosol-forming matrix. Alternatively, the heating element can be an external heating element. The heating element can be part of an aerosol generating apparatus. The heating element can be heated by resistance heating and / or induction heating. Induction heating offers the advantage of eliminating the need for wiring. Therefore, the heating element can be arranged arbitrarily without requiring a large number of electrical connections nearby.

[0019] The heating base element can be understood as the main part of the heating element. As understood, the heating element may include other parts. However, in a preferred embodiment, the heating element comprises only the heating base element and the coating material, as described elsewhere herein. In this way, the heating element can be arranged in a space-saving and compact manner.

[0020] The term "aerosol forming matrix" as used in this disclosure can include materials capable of volatilizing upon heating. Thus, volatile components in aerosol form can be provided. The aerosol forming matrix can include any tobacco-containing material. Additionally or alternatively, the aerosol forming matrix can include one or more of tobacco, tobacco derivatives, expanded tobacco, reconstituted tobacco, or tobacco substitutes. Further, the aerosol forming matrix can include other non-tobacco products, which, depending on the product, may or may not contain nicotine. The aerosol forming matrix can be provided in any desired form, including but not limited to solid, liquid, gel, or wax form, or any other suitable form. The aerosol forming matrix can also be a composition or blend of materials. The aerosol forming matrix may specifically contain components such as nicotine, propylene glycol (PG), and / or vegetable glycerin (VG).

[0021] The heating element disclosed herein can be particularly useful in induction heating devices, although other devices as described elsewhere herein are not excluded. In such devices, internal or external heating elements may not require any wires to be connected to a power source. This allows consumers a simpler and more convenient experience.

[0022] Thermal radiation, as used in this article, can also be referred to as thermal radiation or infrared radiation. Thermal radiation is a form of electromagnetic radiation that may be caused by the movement of charged particles (mainly electrons) within atoms and molecules.

[0023] According to a second embodiment, one or more first components are nicotine, propylene glycol (PG), and / or vegetable glycerin (VG) contained in the aerosol forming matrix.

[0024] The advantage of this embodiment is that it allows for increased thermal radiation to the propylene glycol (PG) and / or vegetable glycerin (VG) contained in the aerosol-forming matrix. This is particularly desirable because these components are especially relevant in the formation of the aerosol to be inhaled. Therefore, heating can be specifically tailored to the first component, making heating more efficient. Consequently, less power can be consumed. Furthermore, the increased heating of only the desired components enhances flavor and mouthfeel.

[0025] In some examples, one or more of the first components may additionally contain other wetting agents and aromatic compounds.

[0026] According to a third embodiment, the coating material is configured to reduce the amount of thermal radiation provided to at least one second component of the aerosol-forming matrix compared to the same heating base element without a coating material, wherein the at least one second component is preferably water contained in the aerosol-forming matrix.

[0027] This embodiment helps to deliver the aerosol to be inhaled with less power. In particular, the second component may be a component that is less related to providing the consumer with taste or flavor.

[0028] Specifically, water has a high specific heat capacity, which means that more energy is required to raise its temperature. Therefore, the energy efficiency of the aerosol generating device is improved because less heat is supplied to the water in the aerosol forming matrix.

[0029] Coating materials

[0030] According to the fourth embodiment, the coating material includes one or more of the following: metal, ceramic, polymer, glass, and preferably aluminum nitride (AlN).

[0031] These materials possess unique properties that make them suitable for use as coatings for heating base elements as described in this article. Metals are durable materials with excellent thermal and electrical conductivity. Ceramics are hard, robust, generally wear-resistant, heat-resistant, and corrosion-resistant, making them ideal for harsh environments. Polymers are versatile and can be designed to offer a wide range of properties. Polymers are typically lightweight, good electrical insulators, and are moisture-proof and chemical-resistant. Glass is a good electrical and thermal insulator, resistant to chemical corrosion, and can be offered in aesthetically pleasing, transparent, or easy-to-clean colored coatings. Aluminum nitride (AlN) is a ceramic material with high thermal conductivity and offers high-temperature stability and resistance to chemical corrosion.

[0032] Furthermore, all of the aforementioned materials have the potential to shift the emission spectrum as desired and as described elsewhere in this document.

[0033] According to the fifth embodiment, the coating material is a non-aerosol forming material.

[0034] Using non-aerosol-forming materials for coatings of heating base elements has several advantages. For example, safety can be improved because the coating material may not generate aerosols when heated. Therefore, the coating material can be harmless to consumers. Additionally, cleanliness can be improved, stability can be enhanced, and it may not interfere with the operation of the device. Furthermore, the heating element may therefore not affect the flavor and taste imparted to consumers by the aerosol-generating matrix.

[0035] In this way, it should be understood that, for example, a portion of the aerosol-forming matrix of an aerosol-forming article may not be understood as a coating material used for heating the base element.

[0036] According to the sixth embodiment, the coating material is an inert material.

[0037] Inert materials are substances or materials that are chemically inactive, non-reactive, or substantially non-reactive under specific conditions or in a given environment. Inert materials are characterized by their stability and / or lack of interaction with other substances or external factors. Inert materials may not chemically react with other substances. Inert materials remain essentially unchanged and do not participate in reactions that could alter their composition or properties. Some non-exhaustive examples of inert materials include metals (such as gold and platinum), as well as certain ceramics and polymers.

[0038] Inert materials used for coatings are particularly advantageous for internal heating elements that are close to water and therefore exceptionally prone to oxidation / rust. However, inert materials used for coatings are also advantageous for external heating elements.

[0039] According to the seventh embodiment, the coating material is configured such that when heated to at least 100°C, preferably at least 200°C, and most preferably at least 250°C, its radiative thermal emission spectrum is more similar to the radiative thermal absorption spectrum of one or more of nicotine, propylene glycol (PG), and vegetable glycerin (VG) than the radiative thermal emission spectrum of the material of the heated base element.

[0040] The advantage of this approach is that radiative heat transfer is particularly increased for one or more of nicotine, propylene glycol (PG), and vegetable glycerin (VG). These substances can be one or more of the first components, as described elsewhere in this document. This reduces overall power consumption, and those components relevant to and / or potentially contributing to consumer flavor and / or mouthfeel can be heated to a higher degree.

[0041] It should be noted that those skilled in the art understand the term "similar to" as used in this embodiment. In particular, it should be understood that corresponding thermal emission and thermal absorption spectra can be substantially similar and / or have similar curvatures. For example, if the electromagnetic radiation emitted by the coating material has considerably high values ​​within a certain wavelength range and / or frequency range, then the thermal absorption spectra of one or more of nicotine, propylene glycol (PG), and vegetable glycerin (VG) can also exhibit considerably high values ​​within the corresponding wavelength and / or frequency ranges. In particular, those skilled in the art can determine whether the corresponding spectra are more similar by comparing the similarity between them with the thermal emission spectra of the material of the heating base element (i.e., without the coating material).

[0042] The radiative thermal emission spectrum of any substance (such as the coating material described herein) refers to the distribution of electromagnetic radiation emitted by the substance at various wavelengths or frequencies due to its temperature.

[0043] The radiative thermal absorption spectra of the first component, the second component, and / or one or more of nicotine, propylene glycol (PG), and vegetable glycerin (VG) describe how they absorb electromagnetic radiation within a wavelength range. A radiative thermal absorption spectrum can be represented as a graph showing the absorption coefficient or intensity as a function of wavelength.

[0044] According to the eighth embodiment, the coating material is configured such that when heated to at least 100°C, preferably at least 200°C, and most preferably at least 250°C, the wavelength of its radiative thermal emission spectrum is close to the maximum emission energy. Compared to the material of the heating base element, these wavelengths are closer to the maximum radiative thermal absorption wavelength of one or more of nicotine, propylene glycol (PG), and vegetable glycerin (VG).

[0045] This embodiment enhances the advantages described in the foregoing embodiments. In particular, radiative heat transfer is increased, especially for one or more of nicotine, propylene glycol (PG), and vegetable glycerin (VG).

[0046] Technicians are able to determine the emission energy, especially the maximum emission energy. For example, the emission energy of an emission spectrum can be determined based on the intensity of radiation emitted within a certain wavelength range or a certain frequency range.

[0047] According to the ninth embodiment, in any of the foregoing embodiments, the coating material has a greater thermal conductivity than the material of the heating base element.

[0048] When the coating material has a higher thermal conductivity than the material of the heating base element, this allows heat to be distributed more evenly across the aerosol-forming matrix. As a result, temperature spikes are mitigated.

[0049] In existing technologies, the primary materials of sensor typically include iron, chromium, etc., which have low thermal conductivity (e.g., below 100 W / mK). Therefore, heat cannot be transferred to the aerosol-forming matrix quickly enough.

[0050] According to the tenth embodiment, in any of the foregoing embodiments, preferably when measured at room temperature (e.g., 20°C or 25°C), the thermal conductivity of the coating material is at least 100 W / (m K), preferably at least 150 W / (m K), more preferably at least 200 W / (m K), more preferably at least 250 W / (m K), and more preferably at least 300 W / (m K).

[0051] The advantage of this approach is that it provides a considerably high thermal conductivity. This induces additional conductive heat transfer in addition to radiative heat transfer. Consequently, heat can be distributed more evenly throughout the aerosol-forming matrix. This mitigates temperature spikes, reducing the risk of ablation of components in the aerosol-forming matrix near the heating element.

[0052] Size and shape

[0053] According to the eleventh embodiment, in any of the foregoing embodiments, the average thickness of the coating material is at least 1 micrometer (μm), preferably at least 2 μm, more preferably at least 5 μm, more preferably at least 10 μm, more preferably at least 20 μm, more preferably at least 30 μm, more preferably at least 40 μm, most preferably at least 50 μm, and / or at most 200 μm, preferably at most 150 μm, more preferably at most 100 μm, more preferably at most 80 μm, more preferably at most 60 μm, and most preferably at most 50 μm.

[0054] The average thickness of the coating material should be sufficiently large to facilitate the delivery of adequate heat radiation. Furthermore, a thicker coating material can be advantageous for protecting the heating base element and / or for providing a durable heating element. Additionally, a thicker coating allows for greater manufacturing tolerances. Therefore, the manufacturing process can be more cost-effective, as manufacturing inaccuracies can be tolerated to a greater extent. On the other hand, the coating material thickness should not be too large; otherwise, the heating element may become quite large and bulky, making it potentially more difficult to handle. Furthermore, when the heating element is placed in an aerosol generating device, the installation space may be reduced, or the handheld aerosol generating device may become too large to be conveniently held by the consumer. Moreover, excessive thickness will require more material, leading to material waste. Accordingly, as proposed herein, a balance should be struck in the thickness of the coating material.

[0055] It should be understood that the eleventh embodiment refers to the average thickness. Typically, the thickness of the coating material on the heating base element can be substantially the same. However, as those skilled in the art will understand, variations are possible.

[0056] It should be noted that when features, aspects, and / or embodiments are described herein using the term "substantially," manufacturing tolerances must be taken into account. In this way, minor deviations can exist during any kind of manufacturing, assembly, etc. Furthermore, manufacturing tolerances, aging effects, or other minor defects may exist. These are all covered by the term "substantially." Although not always explicitly expressed through the use of the term "substantially," it should be understood that elements, parts, units, shapes, and / or similar content described herein may still include such manufacturing tolerances.

[0057] According to the twelfth embodiment, in any of the foregoing embodiments, the coating material is disposed on the outer surface of the heating base element.

[0058] The advantage of this approach is that the coating material can protect the base heating element from wear, tear, corrosion, and / or degradation, thereby extending its service life. Additionally, heating control can be improved. The outer surface can be a surface adjacent to the aerosol-forming matrix. In some examples, the outer surface can be, for example, a surface located within the aerosol-forming matrix and in direct contact with it. Therefore, this embodiment has the advantage of making heat transfer more efficient.

[0059] According to the thirteenth embodiment, in any of the foregoing embodiments, and particularly in the twelfth embodiment, the coating material covers at least 50%, preferably at least 60%, more preferably at least 70%, more preferably at least 80%, more preferably at least 90%, more preferably at least 95%, and most preferably substantially 100% of the outer surface of the heating base element.

[0060] When the coating material covers a significant proportion (if not all) of the outer surface of the heating base element as specified in this embodiment, the advantages mentioned herein can be enhanced over a larger area of ​​the heating base element. These advantages may include improved heat transfer, improved protection, non-stick properties, and a more durable heating base element.

[0061] According to the fourteenth embodiment, in any of the foregoing embodiments, the heating base element has the shape of a strip, cylinder, rod, blade, or pin.

[0062] The technical advantage of heating base elements having shapes such as strips, cylinders, rods, blades, or pins is that they allow for better and / or more uniform heat distribution. These shapes, due to their larger contact surface area, can contribute to more efficient heat transfer. This ensures that the aerosol-forming matrix heated by the heating base element, particularly one or more first components heated by the heating base element, receives a substantially uniform amount of heat. This results in improved heating for consumers, as well as improved flavor and mouthfeel. Furthermore, these specific shapes make it easier to assemble the heating base element into different settings or devices. Therefore, the use cases for heating base elements can be broadened.

[0063] Furthermore, these shapes can contribute to the mechanical integrity of the heating base element. Compared to more complex shapes, cylindrical, rod, and pin shapes can withstand higher physical stresses and are more resistant to bending or breakage. While blades and strips may be more susceptible to certain types of stress, they can be designed and positioned in a way that minimizes these risks. For example, blades and strips can be supported along their length or width to increase strength. Overall, these compact shapes can extend the lifespan of the heating base element, even under continuous or high-volume use, as consumers understand.

[0064] Other suitable shapes covered by this disclosure are flat strips, strips, tubes, pipes, pins, columns, sheets, slats, fragments, needles, or spikes.

[0065] According to the fifteenth embodiment, in any of the foregoing embodiments, the heating element is a sensor.

[0066] The term "receptor" generally refers to a material that absorbs electromagnetic radiation (such as microwaves) and converts it into heat. Heat can be generated by the resistance to current in a high-frequency electromagnetic field.

[0067] The advantage of the sensor is that it is easy to operate and can promote faster and more efficient heating because the electromagnetic field can be directly converted into heat.

[0068] According to the sixteenth embodiment, in any of the foregoing embodiments, the heated base element forms a closed element, particularly without holes or through holes.

[0069] This configuration offers the advantage of improved radiative heat transfer. Furthermore, the advantages mentioned elsewhere in this document are enhanced through this embodiment. Further, this embodiment can contribute to the strength and stability of the heating base element. Additionally, the integrity of the heating base element can be maintained, thereby making it more durable and reliable.

[0070] In the context of this embodiment, a "closed element" can refer to an element having a substantially solid structure, specifically, an element without any macroscopic holes or macroscopic through-holes penetrating its structure. A "hole" in the element refers to an open space or gap within its structure, while a "through-hole" is a hole that completely penetrates the material or part. Thus, when the heating base element is closed, particularly when the heating base element has no holes or through-holes, this means that the heating base element has a substantially solid, continuous structure that is substantially uninterrupted from one side to the other. It should be noted that, as those skilled in the art will understand, small amounts of impurities and / or inclusions such as gases may still cause small holes to appear within the heating base element.

[0071] Aerosol generating products, devices and systems

[0072] The seventeenth embodiment of this disclosure relates to an aerosol generating article comprising: a heating element according to any of the preceding embodiments; and a tobacco segment; wherein the heating element is disposed in or around the tobacco segment.

[0073] It should be noted that the aerosol generating articles described herein may include all aspects and / or embodiments described herein, even if not explicitly described as belonging to aerosol generating articles but described with reference to heating elements. It should also be understood that the features and advantages described with reference to heating elements can equally apply to aerosol generating articles.

[0074] The eighteenth embodiment of this disclosure relates to an aerosol generating apparatus configured to receive an aerosol generating article, the aerosol generating apparatus comprising: a heating element according to any embodiment of the embodiments described herein; and a power source configured to preferably heat the heating element by an electromagnetic field provided by an inductor coil, wherein the heating element is configured to heat an aerosol forming matrix of the aerosol generating article.

[0075] It should be noted that the aerosol generating apparatus described herein may include all aspects and / or embodiments described herein, even if not explicitly described as belonging to an aerosol generating apparatus, but described with reference to aerosol generating articles or heating elements. It should also be understood that the features and advantages described with reference to the aerosol generating apparatus are equally applicable to aerosol generating articles and heating elements.

[0076] The power source can be any suitable power source, such as a DC voltage source, like a battery (e.g., a lithium iron phosphate battery). Alternatively, the power source can be a nickel-cadmium battery, a nickel-metal hydride battery, or a lithium-based battery (e.g., a lithium-cobalt battery, a lithium-iron-phosphate battery, a lithium titanate battery, or a lithium-polymer battery). The power source can be located within the aerosol generating device itself, or it can be another form of charge storage device, such as a capacitor. The power source can be rechargeable and can have a capacity that allows sufficient energy to be stored for one or more typical use cycles. A use cycle can be understood as consuming substantially all of the aerosol-forming matrix of the aerosol generating article. If liquid consumables are used (which are also covered by this disclosure), a use cycle can be understood as consuming substantially all of the liquid.

[0077] It should be understood that this power supply requires less capacity than existing power supplies because the heating process is more efficient due to the coating materials described elsewhere in this document.

[0078] The nineteenth embodiment of this disclosure relates to an aerosol generation system, which includes: an aerosol generation article according to the seventeenth embodiment; and an aerosol generation apparatus.

[0079] It should be noted that the aerosol generation system described herein may include all aspects and / or embodiments described herein, even if not explicitly described as belonging to an aerosol generation system but described with reference to an aerosol generation article or heating element. It should also be understood that the features and advantages described with reference to the aerosol generation system are equally applicable to aerosol generation articles and heating elements. Attached Figure Description

[0080] In the following description, preferred embodiments are illustrated by way of example only. Refer to the following figures:

[0081] Figure 1 A heating element for heating an aerosol-forming matrix of an aerosol-generating article according to an embodiment of the present invention is shown.

[0082] Figure 2 An aerosol generating apparatus and aerosol generating system according to embodiments of the present invention are shown.

[0083] Figure 3 Various emission and absorption spectra are shown to illustrate the invention. Detailed Implementation

[0084] definition

[0085] As used herein, the term "aerosol generating article" may also be referred to as a consumable or consumable product. Such an aerosol generating article may include an aerosol forming matrix that can be heated to generate aerosols and / or vapors available for inhalation by a user.

[0086] The term "sensor" typically refers to a material that absorbs electromagnetic radiation (such as microwaves) and converts it into heat.

[0087] The embodiments shown in the accompanying drawings

[0088] The invention is described in more detail below with reference to the accompanying drawings. However, the invention can also be used in other embodiments not explicitly disclosed below. As detailed below, the embodiments are compatible with each other, and a single feature of one embodiment may be applied to another.

[0089] Throughout the accompanying drawings and description, unless otherwise stated, the same reference numerals refer to the same elements. The drawings may not be drawn to scale, and the relative dimensions, scale, and depiction of elements in the drawings may be exaggerated for clarity, illustration, and convenience. The drawings do not limit the scope of the claims but only support an understanding of the invention.

[0090] Figure 1 A heating element 10 according to an embodiment of the present invention is shown for heating an aerosol forming matrix 5 of an aerosol generating article 1. The heating element 10 is used to heat the aerosol forming matrix 5 of the aerosol generating article 1 received in an aerosol generating apparatus 100. The heating element 10 includes a heating base element 11 configured to heat the aerosol forming matrix 5 at least by means of thermal radiation. The heating element 10 also includes a coating material 12 disposed on the heating base element 11. The coating material 12 is configured to increase the amount of thermal radiation provided to one or more first components of the aerosol forming matrix 5 compared to the same heating base element 10 without the coating material 12.

[0091] The coating material 12 can be applied to the heating base element 11 in various ways. For example, the coating can be applied via atomic layer deposition, PVD, CVD, plasma sputtering, plasma coating, dip coating, etc. In one example, the heating base element 11 can be a metal sensor.

[0092] One or more first components may be nicotine contained in the aerosol forming matrix 5 (exemplary absorption spectrum of nicotine in...) Figure 3 As shown in the figure, propylene glycol (PG) and / or vegetable glycerin (VG) are indicated by reference numeral 55.

[0093] Propylene glycol (PG) is commonly used in aerosol generating devices, and its primary function in these devices is as a solvent or carrier for nicotine and / or flavorings in the aerosol-forming matrix 5. When heated in an aerosol generating device, propylene glycol can be converted into an inhalable aerosol. Propylene glycol can have a low vaporization point and can contribute to producing a "throat hit." This sensation, similar to that of smoking traditional tobacco, is likely sought by many consumers of these devices.

[0094] Vegetable glycerin (VG), also known as glycerol or glycerol, is a clear, odorless, and viscous liquid derived from vegetable oils (typically palm oil, soybean oil, or coconut oil). Vegetable glycerin is a carbohydrate molecule called a sugar alcohol. Due to its unique properties and versatility, vegetable glycerin is widely used in various industries.

[0095] Vegetable glycerin is also used as a base liquid in e-liquids for inhalation. Vegetable glycerin helps to produce vapor when heated and is often used in combination with flavorings and nicotine.

[0096] The coating material 12 may include one or more of the following: metal, ceramic, polymer, glass, and preferably aluminum nitride (AlN) (exemplary emission spectra of AlN are shown in...). Figure 3 As shown in the figure (indicated by reference numeral 51), ceramics are a large class of materials primarily composed of inorganic compounds, typically including metal oxides, nonmetallic compounds, and sometimes crystalline minerals. Ceramics are typically characterized by their high melting point, hardness, and brittleness. Ceramics can have crystalline or amorphous (non-crystalline) structures. Glass is an amorphous (non-crystalline) solid material. Glass is typically made from mixtures of various inorganic materials, including silicon dioxide, soda ash (sodium carbonate), and lime (calcium oxide).

[0097] While all materials emit thermal radiation when heated, the specific emission spectrum (i.e., the distribution of emitted energy at different wavelengths) can depend on the material's emissivity. Different materials will have different spectral shapes and peak wavelengths in their emission spectra due to differences in their emissivity characteristics (see further below). Figure 3 (A more detailed description).

[0098] The coating material 12 can have a higher thermal conductivity than the material of the heating base element 11. For example, preferably when measured at room temperature (e.g., 20°C or 25°C), the thermal conductivity of the coating material 12 can be at least 100 W / (m K), preferably at least 150 W / (m K), more preferably at least 200 W / (m K), more preferably at least 250 W / (m K), and more preferably at least 300 W / (m K). A higher thermal conductivity value for the coating material 12 means that its ability to efficiently conduct heat is enhanced. This can become significant when such a coating material 12 is applied to the surface of the heating base element 11. The advantages of increased thermal conductivity of the coating material 12 can include improved heat transfer, faster heating, higher energy efficiency, better performance, and avoidance of hot spots.

[0099] like Figure 1 As exemplarily indicated, the average thickness of the coating material 12 is t. The thickness can be at least 1 micrometer (μm), preferably at least 2 μm, more preferably at least 5 μm, more preferably at least 10 μm, more preferably at least 20 μm, more preferably at least 30 μm, more preferably at least 40 μm, most preferably at least 50 μm, and / or at most 200 μm, preferably at most 150 μm, more preferably at most 100 μm, more preferably at most 80 μm, more preferably at most 60 μm, and most preferably at most 50 μm.

[0100] As can be seen, the coating material 12 is disposed on the outer surface of the heating base element 11. Furthermore, the coating material 12 can cover at least 50%, preferably at least 60%, more preferably at least 70%, more preferably at least 80%, more preferably at least 90%, more preferably at least 95%, and most preferably substantially 100% of the outer surface of the heating base element 11.

[0101] The heating base element 11 can have the shape of a strip, cylinder, rod, blade, or pin. In particular, the heating element 10 can be a sensor. Further, such as... Figure 1 As shown, the heating base element 11 forms a closed element, specifically without holes and / or without through holes.

[0102] Figure 2 An aerosol generating apparatus 100 and an aerosol generating system 200 according to an embodiment of the present invention are shown.

[0103] System 200 includes an aerosol generating device 100 and an aerosol generating article 1, the aerosol generating article including an aerosol forming matrix 5. The aerosol generating device 100 includes a cavity 20, such as a heated cavity 20 for receiving the aerosol generating article 1. Furthermore, the aerosol generating device 100 includes a power source 101 (e.g., a battery) configured to supply current to a heating coil 102 for inductively heating a heating element 10, thereby generating an aerosol by heating the aerosol forming matrix 5 of the aerosol generating article 1 to be inhaled by a consumer. The power source 101 can be any suitable power source, such as a DC voltage source.

[0104] although Figure 2 An embodiment is shown in the internal heating element 10, but various other configurations are covered in this disclosure as described elsewhere herein.

[0105] As a specific example and mentioned only for the purpose of illustrating the invention, the heating element 10 may be an external sensor. Such an external sensor refers to a component or material placed outside the main heating element of the aerosol generating device 100 to help heat and vaporize the aerosol forming matrix 5 received in the device 100.

[0106] As a specific example and mentioned only for the purpose of illustrating the invention, the heating element 10 may be an internal heating element of the aerosol generating apparatus 100. Such an internal heating element 10 may be inserted into the aerosol forming matrix 5 of the heated aerosol generating article 1, such that the internal heating element may be in direct contact with the aerosol forming matrix 5.

[0107] Figure 3 Various emission and absorption spectra are shown to illustrate the invention in various embodiments.

[0108] Figure 3 The x-axis in the figure shows the wavelength in µm. The left y-axis shows the emissivity in % and the right y-axis shows the absorptivity in % of the wavelength. Reference numeral 50 shows the emission spectrum of stainless steel, which can be conventionally used as a material for the heating base element 11. As can be seen, the emission spectrum of stainless steel 50 does not provide a very high emissivity (e.g., radiant energy) at the wavelengths depicted. Reference numeral 51 shows the emission spectrum of aluminum nitride (AlN), and reference numeral 52 shows the emission spectrum of aluminum nitride (AlN) on stainless steel. Reference numeral 55 shows the absorption spectrum of nicotine, which may be a first component as described elsewhere herein. Reference numeral 56 shows the absorption spectrum of water, which may be a second component as described elsewhere herein.

[0109] As can be seen, when AlN is used as coating material 12 on the heating base element 11, this embodiment is configured to increase the coating on one or more first components (e.g., ...) compared to the same heating base element 11 without coating material 12. Figure 3 The amount of thermal radiation provided by nicotine (55) is depicted in the figure. This becomes apparent when comparing graph 52 with graph 50. One or more of the first components may include nicotine, propylene glycol (PG), and / or vegetable glycerin (VG).

[0110] Furthermore, the coating material 12 is configured to reduce the amount of thermal radiation provided to at least one second component of the aerosol-forming matrix 5 compared to the same heating base element 11 without the coating material 12. The second component can be water. Consequently, less water vapor is generated. This is advantageous because inhaling large amounts of water vapor can lead to a less than satisfactory user experience. Water vapor may not carry flavor as well as other solvents such as propylene glycol or vegetable glycerin, which could alter the taste. Moreover, inhaling large amounts of water vapor can be uncomfortable and even potentially harmful to consumers. Therefore, it is particularly advantageous to reduce the heat supplied to the water, as described herein.

[0111] As can be seen, the coating material 12 can be configured such that when heated to at least 100°C, preferably at least 200°C, most preferably at least 250°C, the radiative thermal emission spectrum is more similar to the radiative thermal absorption spectrum of one or more of nicotine, propylene glycol PG, and vegetable glycerin VG than the radiative thermal emission spectrum of the material of the heated base element 11.

[0112] As can be seen, the coating material 12 can be further configured to have a radiative thermal emission spectrum with wavelengths close to the maximum emission energy when heated to at least 100°C, preferably at least 200°C, and most preferably at least 250°C. These wavelengths are closer to the maximum radiative thermal absorption wavelengths of one or more of nicotine, propylene glycol PG, and vegetable glycerin VG compared to the material of the heating base element 11.

[0113] As in Figure 3 As can be seen, water may exhibit significant absorption bands in the infrared region due to its vibrational modes, particularly near 3 micrometers (μm) and 6 μm. These absorption bands are frequently used in remote sensing and atmospheric science to study the water vapor content in the atmosphere.

[0114] Nicotine is a chemical compound that, based on its molecular structure, may exhibit absorption characteristics in different parts of the electromagnetic spectrum, but its absorption spectrum may be quite different from that of water (e.g., Figure 3 As seen in the attached diagram, 55 represents nicotine, and 56 represents water.

[0115] As described elsewhere, the determination of the emission energy is known to those skilled in the art. To determine the emission energy, one can integrate the product of the intensity at each wavelength (I(λ) or I(ν)) with the corresponding differential wavelength (dλ) or frequency (dν) over the range of interest in the emission spectrum. Mathematically, this can be expressed as the following integral:

[0116] For wavelength (λ) spectrum: Emission energy (E) = ∫ I(λ) dλ.

[0117] For the frequency (ν) spectrum: Emission energy (E) = ∫ I(ν) dν.

[0118] In a particular example, the heating element 10 may be a sensor, such as an internal or external sensor, and the coating 12 may be entirely or at least partially disposed on the heating base element 11 with at least one coating material 12. It may be particularly advantageous to use a ceramic material for the coating that has an emission spectrum matching the absorption spectra of one or more of nicotine, PG, and VG while avoiding the absorption spectrum of water. In a preferred embodiment, the thickness of the coating material 12 may be from 1 µm to 2 µm, and the coating material 12 may be AlN.

[0119] It will be apparent to those skilled in the art that numerous modifications and variations of the described examples and embodiments are possible in accordance with the foregoing teachings. The disclosed examples and embodiments are presented for illustrative purposes only. Other embodiments may include some or all of the features disclosed herein. Therefore, it is intended to cover all such modifications and alternative embodiments that may fall within the true scope of the invention.

[0120] List of reference numerals

[0121] .

Claims

1. A heating element for heating an aerosol-forming matrix of an aerosol-generating article received in an aerosol-generating apparatus, the heating element comprising: A heating base element is configured to heat the aerosol-forming matrix at least by means of thermal radiation; as well as A coating material is applied to the heating base element; The coating material is configured to increase the amount of thermal radiation provided to one or more first components of the aerosol-forming matrix compared to the same heating base element without the coating material. The coating material is configured to reduce the amount of thermal radiation provided to at least one second component of the aerosol-forming matrix compared to the same heating base element without the coating material. The at least one second component is preferably water contained in the aerosol forming matrix.

2. The heating element according to the preceding claim, wherein, The one or more first components are nicotine, propylene glycol (PG), and / or vegetable glycerin (VG) contained in the aerosol forming matrix.

3. The heating element according to any one of the preceding claims, wherein, The coating material includes one or more of the following: metal, ceramic, polymer, glass, and preferably aluminum nitride (AlN).

4. The heating element according to any one of the preceding claims, wherein, The coating material is a non-aerosol forming material.

5. The heating element according to any one of the preceding claims, wherein, The coating material is an inert material.

6. The heating element according to any one of the preceding claims, wherein, The coating material is configured such that when heated to at least 100°C, preferably at least 200°C, and most preferably at least 250°C, its radiative thermal emission spectrum is more similar to the radiative thermal absorption spectrum of one or more of nicotine, propylene glycol (PG), and vegetable glycerin (VG) than that of the material of the heating base element.

7. The heating element according to any one of the preceding claims, wherein, The coating material is configured such that when heated to at least 100°C, preferably at least 200°C, and most preferably at least 250°C, the wavelengths of its radiative thermal emission spectrum are close to the maximum emission energy, and these wavelengths are closer to the maximum radiative thermal absorption wavelengths of one or more of nicotine, propylene glycol (PG), and vegetable glycerin (VG) compared to the material of the heating base element.

8. The heating element according to any one of the preceding claims, wherein, Compared to the material of the heating base element, the coating material has a higher thermal conductivity.

9. The heating element according to any one of the preceding claims, wherein, Preferably, when measured at room temperature such as 20°C or 25°C, the thermal conductivity of the coating material is at least 100 W / (m K), preferably at least 150 W / (m K), more preferably at least 200 W / (m K), more preferably at least 250 W / (m K), and more preferably at least 300 W / (m K).

10. The heating element according to any one of the preceding claims, wherein, The coating material has an average thickness of at least 1 micrometer (μm), preferably at least 2 μm, more preferably at least 5 μm, more preferably at least 10 μm, more preferably at least 20 μm, more preferably at least 30 μm, more preferably at least 40 μm, and most preferably at least 50 μm, and / or The maximum size is 200 μm, preferably 150 μm, more preferably 100 μm, more preferably 80 μm, more preferably 60 μm, and most preferably 50 μm.

11. The heating element according to any one of the preceding claims, wherein, The coating material is applied to the outer surface of the heating base element.

12. The heating element according to the preceding claim, wherein, The coating material covers at least 50%, preferably at least 60%, more preferably at least 70%, more preferably at least 80%, more preferably at least 90%, more preferably at least 95%, and most preferably substantially 100% of the outer surface of the heating base element.

13. The heating element according to any one of the preceding claims, wherein, The heating base element has the shape of a strip, cylinder, rod, blade, or pin.

14. The heating element according to any one of the preceding claims, wherein, The heating element is a sensor.

15. The heating element according to any one of the preceding claims, wherein, The heating base element forms a closed element, specifically without holes or through holes.

16. An aerosol-generating article, the aerosol-generating article comprising: Heating element according to any one of the preceding claims; as well as Tobacco segment; The heating element is arranged in or around the tobacco segment.

17. An aerosol generating apparatus configured to receive an aerosol generating article, the aerosol generating apparatus comprising: Heating element according to any one of claims 1 to 9, 11, or 14; as well as A power source configured to preferably heat the heating element via an electromagnetic field provided by an inductor coil, wherein the heating element is configured to heat the aerosol forming matrix of the aerosol generating article.

18. An aerosol generation system, the aerosol generation system comprising: The aerosol generating article according to claim 15, and Aerosol generating device.

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