Method and apparatus for aligning elongated susceptor elements within an aerosol-forming substrate

Abstract

A method for aligning elongated susceptor elements in or on an aerosol-forming substrate for use in an induction-heatable aerosol-generating article includes providing an aerosol-forming substrate in the form of a sheet material (4). The aerosol-forming substrate comprises a plurality of elongated susceptor elements (3). The sheet material (4) is disposed near a magnetic alignment device (5). An alignment magnetic field is applied to the aerosol-forming substrate (4) by the magnetic alignment device (5). The alignment magnetic field pulls the elongated susceptor elements (3) toward a reference axis of the sheet material (4) and aligns them along the alignment magnetic field, at least partially.

Description

Technical Field

[0001] The present disclosure relates to a method of aligning elongated susceptor elements within an aerosol-forming substrate for use in an inductively heatable aerosol-generating article. The present disclosure further relates to an apparatus for aligning elongated susceptor elements within an aerosol-forming substrate, particularly for use in the method according to the present disclosure.

Background Art

[0002] Aerosol generation systems that use inductive heating to generate an inhalable aerosol are generally known from the prior art. Such systems may comprise an inductive heating aerosol generation device and a separate aerosol-generating article for use with the device. Among other components, the article may include an aerosol-forming substrate having the ability to form an inhalable aerosol when heated, and an inductively heatable susceptor arrangement that is thermally proximate or physically in direct contact with the substrate to heat the substrate. Inductive heating of the susceptor arrangement is achieved by the interaction of the susceptor arrangement with an alternating magnetic field provided by the aerosol generation device. During operation, the alternating magnetic field induces at least one of eddy currents or hysteresis losses in the susceptor arrangement, heating the latter to a temperature sufficient to release volatile compounds from the heated substrate, and then cooling to form an aerosol.

[0003] Depending on the type of substrate and the shape of the article, different configurations of susceptor element arrangements are known. For example, an article may comprise a single solid susceptor element, such as a susceptor flake, embedded within a solid or gel-like aerosol-forming substrate within the substrate portion of the article. While solid susceptor elements are inexpensive and readily available, they form a single central heat source, which can result in a heterogeneous temperature distribution across the substrate portion. This is because direct heating of the substrate occurs only in the immediate vicinity of the susceptor element, while the peripheral regions of the substrate portion are heated only indirectly through heat conduction across adjacent substrate layers. In particular, a high-temperature gradient can overheat the inner regions of the substrate portion near the susceptor element, while the temperature of the peripheral regions of the substrate portion may be too low to volatilize the substrate. Furthermore, the heating efficiency of this configuration is quite sensitive to the proper positioning of the susceptor element within the substrate. All of these factors can lead to inefficient utilization of the aerosol-forming substrate. Alternatively, articles containing spherical or quasi-spherical susceptor particles homogeneously obstructed throughout the aerosol-forming substrate have been proposed. While this leads to more homogeneous heating of the substrate, the heating efficiency of this susceptor configuration is limited, which can also affect extraction efficiency. Another alternative is to provide elongated susceptor elements distributed throughout the aerosol-forming substrate or deposited on the main surface of the aerosol-forming substrate. This leads to more uniform heating of the aerosol-forming substrate, but it has been found that proper alignment of the elongated susceptor elements with respect to the applied alternating magnetic field can further increase heating efficiency.

[0004] Therefore, it is desirable to have an induction-heatable aerosol-forming substrate and an apparatus for producing such an aerosol-forming substrate that has the advantages of prior art solutions while mitigating their limitations. In particular, it is desirable to have an aerosol-forming substrate that includes at least partially aligned elongated susceptor elements to provide more efficient heating and utilization of the aerosol-forming substrate. [Overview of the project]

[0005] According to one aspect of the present disclosure, a method is provided for aligning elongated susceptor elements in or on an aerosol-forming substrate for use in an induction-heatable aerosol-generating article. The method comprises the steps of providing an aerosol-forming substrate in the form of a sheet material, the aerosol-forming substrate comprising a plurality of elongated susceptor elements. The sheet material is then placed near a magnetic alignment device in a subsequent step. An alignment magnetic field is then applied to the aerosol-forming substrate by the magnetic alignment device, and the alignment magnetic field aligns the elongated susceptor elements by attracting them at least partially along the alignment magnetic field with respect to a reference axis of the sheet material.

[0006] As used herein, the term “elongated susceptor element” refers to a susceptor element in which one of its principal dimensions is greater than the two remaining dimensions perpendicular to the principal dimension. Thus, an elongated susceptor element may also be referred to as a 1D-elongated susceptor element (a synonym for a one-dimensionally elongated susceptor element) or a quasi-1D susceptor element (a synonym for a quasi-one-dimensional susceptor element). In particular, the term “elongated susceptor element” may refer to a susceptor element in which the length dimension is greater than any cross-sectional dimension perpendicular to the length dimension. More specifically, a 1D-elongated susceptor element may be an elongated susceptor element or an elongated spherical susceptor element.

[0007] The present invention is described herein in relation to elongated susceptor elements having a length dimension greater than any transverse dimension perpendicular to the length dimension; that is, a 1D-elongated susceptor element in which one principal dimension is greater than the two remaining dimensions perpendicular to the principal dimension. This definition also applies equally to susceptor elements in which two (perpendicular) principal dimensions are greater than the remaining dimensions perpendicular to the principal dimensions. Such susceptor elements may also be referred to as 2D-elongated susceptor elements. In particular, the present invention applies equally to susceptor elements having a width dimension greater than the length dimension and the thickness dimension, where the length dimension may be greater than or substantially similar to the width dimension. More specifically, the present invention applies equally to susceptor elements having one of the following shapes: an obtuse cylindrical shape such as a coin shape, an obtuse elliptical shape such as a lens shape, or a thin or plate shape. For these susceptor elements, the same features and advantages described herein for (1D-) elongated susceptor elements apply equally, and can be similarly expressed by essentially replacing the term "(1D-) elongated susceptor element's maximum length dimension" with "the maximum dimension in the two principal dimensions of a 2D- elongated susceptor element," and "(1D-) elongated susceptor element's maximum cross-sectional dimension" with "the maximum dimension in the remaining (non-principal) direction of a 2D- elongated susceptor element."

[0008] Compared to a single solid susceptor element, the use of multiple elongated susceptor elements dispersed throughout the aerosol-forming substrate is advantageous in that it results in a more uniform thermal distribution across the substrate without any significant temperature gradients across different substrate regions. Furthermore, if the susceptor material of the susceptor elements has high thermal conductivity, the homogeneity of the thermal distribution is further enhanced by the fact that a substrate containing multiple dispersed susceptor elements exhibits increased equivalent thermal conductivity compared to a substrate without susceptor elements or with only a single solid susceptor element. Moreover, to achieve a homogeneous thermal distribution, the proposed susceptor arrangement is less sensitive to the positioning of the susceptor elements compared to a single solid susceptor element.

[0009] Most importantly, the geometric shape of the susceptor element, particularly its relative dimensions, has been found to have a significant impact on heating efficiency and, consequently, substrate extraction efficiency. In this regard, elongated susceptor elements have been found to exhibit a lower tendency towards demagnetization compared to more equidimensional susceptor elements, such as spherical or quasi-spherical susceptor particles. This can be explained as follows: When a susceptor element is placed in an external magnetic field, it is progressively magnetized. As the external magnetic field increases, the internal magnetization also increases. This process continues until the magnetization reaches the magnetic saturation point of the material, beyond which no further magnetization occurs. As a result, the magnetization of the susceptor element causes an accumulation of magnetic charge density at both ends of the susceptor element, as seen in the direction of the external magnetic field. Consequently, the susceptor element generates a magnetic field that causes self-interaction with its material. This magnetic field is aligned in the same direction as the external magnetic field but at the opposite point, and is therefore called demagnetization. Demagnetization depends on the geometric shape of the susceptor element, but not on its absolute dimensions. When a susceptor element responds to an external magnetic field change, demagnetization is generally assumed to be proportional to the magnetization in each direction, related by a geometrically dependent proportionality constant known as the demagnetization coefficient. The demagnetization coefficient depends not only on the shape of the susceptor element but also on its relative orientation to the external magnetic field. To this extent, it has been found that an external magnetic field extending through elongated susceptor elements, such as those in the shape of fibers or thin rods with length dimensions significantly larger than any transverse dimension perpendicular to the length dimension, generates weaker or negligible demagnetization compared to non-elongated (equal-dimension) susceptor elements, such as spherical or quasi-spherical susceptor elements. This is intuitively understandable because, in properly aligned elongated susceptor elements, the magnetic charge densities accumulated at both ends of the susceptor element are more spatially separated from each other. As a result, the demagnetization significantly reduces its intensity, and therefore has less impact on the magnetization field, which is the cause of power loss. Consequently, power loss and therefore heating efficiency are greater in elongated susceptor elements compared to non-elongated (equal-dimension) susceptor elements such as spherical or quasi-spherical susceptor elements.This is especially true when the orientation of the magnetic field is substantially parallel to the length dimension of the elongated susceptor element, in which heating performance is maximized. However, it has been found that the elongated susceptor element does not necessarily need to be perfectly aligned parallel to the direction of the external magnetic field. Even when the susceptor element is aligned within a certain angular range with respect to the orientation of the external magnetic field, the overall heating performance is still higher than that of a susceptor arrangement where the susceptor elements are randomly oriented.

[0010] As described above, the aerosol-forming substrate includes a plurality of elongated susceptor elements. Preferably, the elongated susceptor elements can be deposited on the main surface of the sheet material before or during the application of an aligned magnetic field to the aerosol-forming substrate containing the elongated susceptor elements.

[0011] To increase the adhesion of elongated susceptor elements to the main surface of the sheet material, an adhesive may be applied to the main surface of the sheet material. The adhesive may be applied before the susceptor elements are deposited thereon. Alternatively, the adhesive may be applied to the main surface of the sheet material after the elongated susceptor elements have been at least partially aligned. Thus, the adhesive can advantageously avoid displacement of the at least partially aligned elongated susceptor elements during subsequent processing of the sheet material. Preferably, the adhesive contains glycerol.

[0012] Displacement of the elongated susceptor elements may also be avoided, or in addition to, by embedding the elongated susceptor elements at least partially within the sheet material, for example, by a pressurizing device and / or rollers, instead of applying adhesive.

[0013] Alternatively or additionally, the elongated susceptor elements may be dispersed throughout an aerosol-forming substrate provided as a sheet material. In this case, the aerosol-forming substrate may be provided with viscosity that allows the elongated susceptor elements dispersed through it to move and at least partially align when subjected to an aligning magnetic field. The aerosol-forming substrate is preferably dried, strengthened, and / or cured after the elongated susceptor elements have been at least partially aligned to avoid displacement of the elongated susceptor elements during subsequent processing of the sheet material.

[0014] The method may include providing an aerosol-forming substrate containing a plurality of elongated susceptor elements to or passing through a magnetic alignment device. The method may also include transporting the aerosol-forming substrate containing a plurality of elongated susceptor elements to the magnetic alignment device.

[0015] The method may include supplying elongated susceptor elements to an aerosol-forming substrate upstream of a magnetic alignment device.

[0016] Since the overall heating performance of elongated susceptor elements increases as the deviation from substantially parallel alignment with the alternating magnetic field used for induction heating decreases, elongated susceptor elements may be aligned such that the angle between the length dimension of the elongated susceptor element and the reference axis is in the range of +30° to -30°, preferably +25° to -25°, specifically +10° to -10°. Thus, an aerosol-forming substrate with increased heating performance can be provided. As used herein, the terms "(at least) partially aligned" or "(at least) partially aligned" refer to this type of alignment within the angular range defined above.

[0017] As described above, heating performance is maximized for substantially parallel alignment. Therefore, it is preferable that the elongated susceptor elements be aligned substantially parallel to the reference axis. As used herein, the term “substantially parallel” is understood to mean “a deviation of ±5° from parallel alignment.”

[0018] The reference axis of the sheet material may be parallel to the sheet material itself.

[0019] In general, elongated susceptor elements may be randomly oriented within an aerosol-forming substrate, but in the case of random arrangement, the overall heating performance is lower than that of an assembly of elongated susceptor elements aligned within a specific angular range or substantially parallel to the alternating magnetic field. This is because, when considering an assembly of susceptor elements, the overall heating performance of an assembly of randomly oriented elongated susceptor elements is still statistically higher than that of an assembly of non-elongated susceptor elements.

[0020] The present disclosure provides a method / apparatus that enables the easy, at least partially, alignment of elongated susceptor elements deposited on the main surface of a sheet material and / or dispersed throughout an aerosol-forming substrate provided as a sheet material, thus enabling the production of an induction-heatable aerosol-generating article with increased heating performance.

[0021] Whenever a number or range is given for multiple objects, such as multiple susceptor elements, this means that the number or range applies to at least 60 percent, in particular at least 70 percent, more specifically at least 80 percent, in particular at least 90 percent of the multiple objects, preferably all of the multiple objects. For example, the disclosure states that elongated susceptor elements are aligned such that the angle between the length dimension of the elongated susceptor element and the reference axis is within the range of +A degrees to -A degrees, which means that at least 60 percent, in particular at least 70 percent, more specifically at least 80 percent, in particular at least 90 percent of all elongated susceptor elements are aligned such that the angle between the length dimension of the elongated susceptor element and the reference axis is within the range of +A degrees to -A degrees.

[0022] The throughput of the method according to this disclosure may be increased by moving the magnetic alignment device and the sheet material relative to each other during the alignment of the elongated susceptor elements, thus enabling the alignment of the elongated susceptor elements at least partially over a large portion of the sheet material. This is particularly advantageous when the sheet material is provided as a continuous substrate sheet.

[0023] In particular, during the alignment of elongated susceptor elements, the sheet material may be moved in the transport direction relative to (especially through) the magnetic alignment device, either continuously or in steps. The transport direction is preferably parallel to the plane defined by the sheet material or parallel to the plane in contact with the sheet material at the alignment location.

[0024] As used herein, the term “alignment location” refers to the current-driven (surface) portion of a sheet material to which an elongated susceptor element is subjected to an aligning magnetic field provided by a magnetic alignment device.

[0025] The conveying direction may preferably be substantially parallel to the reference axis of the sheet material. Therefore, a sheet material having elongated susceptor elements that are at least partially aligned with respect to both the reference axis and the conveying direction may be provided in particular by providing the sheet material as a continuous substrate sheet, thereby enabling increased alignment performance when using the method according to this disclosure.

[0026] The continuous or stepwise movement of the sheet material (especially the material passing through it) in the conveying direction relative to the magnetic alignment device can be achieved by a base conveyor belt or one or more rollers.

[0027] The magnetic alignment device is preferably positioned vertically below the sheet material at the alignment location.

[0028] As used herein, the term “displaced vertically downward” is understood to mean the projection of the plane of the sheet material, or the projection of the plane that is in contact with the sheet material at the alignment point below the sheet material.

[0029] However, of course, according to the present disclosure, the magnetic alignment device may be disposed anywhere as long as the alignment magnetic field provided by the alignment magnetic device is disposed and oriented to attract and align the elongated susceptor element with respect to the reference axis, which means that the alignment magnetic field extends through the sheet material at the alignment location and at least partially aligns the elongated susceptor element.

[0030] The alignment of the elongated susceptor element may preferably be achieved with a magnetic alignment device comprising at least one magnetic roller. The magnetic roller is a simple component that enables the alignment magnetic field to be provided in a desired direction and can be flexibly disposed according to requirements and product characteristics. For example, the magnetic roller may be part of a substrate conveyor belt or may be configured as a roller used to convey the sheet material.

[0031] The magnetic roller may be a permanent magnetic roller or an electromagnetic roller and may include one or more permanent magnets and / or one or more electromagnets. The plurality of magnets may be fixedly disposed or may rotate, particularly at the same rotational speed as the magnetic roller.

[0032] When the magnetic roller includes a plurality of permanent magnets, the plurality of permanent magnets may be circumferentially disposed around the rotational axis of the magnetic roller within the peripheral portion of the magnetic roller.

[0033] Similarly, when the magnetic roller includes a plurality of electromagnets, the plurality of permanent magnets may be circumferentially disposed around the rotational axis of the magnetic roller within the peripheral portion of the magnetic roller.

[0034] At least partial alignment of the elongated susceptor elements may be achieved, in particular, in a configuration in which the magnetic field outside the magnetic roller extends at least partially circumferentially around the magnetic roller. In particular, if multiple permanent magnets and / or electromagnets are included by the magnetic roller, the magnets may be configured such that the magnetic field extends at least partially circumferentially around the magnetic roller outside the magnetic roller. Preferably, the multiple permanent magnets and / or electromagnets may be configured such that the outermost poles of the magnets alternately have north and south poles with respect to the radial direction of the magnetic roller, i.e., the magnets are arranged such that the outermost north pole of one magnet is followed by the outermost south pole of another magnet along the circumferential direction of the magnetic roller. In particular, adjacent magnets may alternately have outermost north and south poles. If electromagnets are used, they may be configured to provide an alignment magnetic field only over the circumferential portion of the magnetic roller and / or to be synchronized with the rotation of the magnetic roller for that purpose.

[0035] Alternatively, at least partial alignment of the elongated susceptor elements may be achieved by a magnetic field outside the magnetic roller that extends parallel to the axis of rotation of the magnetic roller. In this case, the elongated susceptor elements are at least partially aligned perpendicular to the conveying direction, i.e., the reference axis is positioned perpendicular to the conveying direction. Therefore, it is preferable that the elongated susceptor elements be at least partially aligned such that the angle between the length dimension of the elongated susceptor elements and the direction perpendicular to the conveying direction is in the range of +30 to -30 degrees, preferably +25 to -25 degrees, and particularly +10 to -10 degrees. It is also preferable that the elongated susceptor elements are aligned substantially parallel to each other and perpendicular to the conveying direction.

[0036] The width of the sheet material may be greater than the width of the elongated susceptor element. For example, the width of the sheet material may be at least 1 centimeter, or at least 5 centimeters, or at least 10 centimeters, or at least 15 centimeters.

[0037] To align elongated susceptor elements across the entire width of the sheet material, the magnetic alignment device may be configured such that its lateral dimension substantially corresponds to the lateral dimension of the sheet material.

[0038] The alignment magnetic field may be applied to the sheet material continuously or intermittently, and at a constant or pulsed magnetic field strength and / or magnetic flux density. For example, the magnetic alignment device may include permanent magnetic rollers, thereby providing a continuous alignment magnetic field. The magnetic alignment device may also include electromagnetic rollers configured to provide a continuous or intermittent alignment magnetic field. In yet another embodiment, the magnetic alignment device may include at least two electromagnets, and the alignment magnetic field may be generated intermittently or pulsed between at least two electromagnets, preferably synchronized with the transport speed of the sheet material moving relative to the magnetic alignment device. This is particularly advantageous in order to avoid displacement when at least partially aligned elongated susceptor elements are moving outside the alignment magnetic field.

[0039] The aerosol-forming substrate may preferably be made from a substrate slurry cast in the form of a sheet material, and the elongated susceptor elements may be deposited on the main surface of the sheet material and / or dispersed throughout the sheet material, in particular before the cast substrate slurry is dried. Depending on the hardness of the cast substrate slurry, the elongated susceptor elements may be at least partially embedded in the substrate sheet after or during deposition prior to the alignment process.

[0040] As already mentioned above, the aerosol-forming substrate in the form of a sheet material may be a continuous substrate sheet, thus enabling the continuous alignment of elongated susceptor elements on / within the continuous substrate sheet and increasing the throughput of the method according to this disclosure.

[0041] To further improve the production of aerosol-forming substrates, elongated susceptor elements may be aligned during or after crimping a continuous substrate sheet, particularly during or after crimping a continuous substrate sheet in the longitudinal direction. The longitudinal direction may be the mechanical direction of the continuous substrate sheet, and is preferably parallel to the conveying direction. Cremation may be carried out by passing the sheet material between corrugated crimping rollers. Alignment of elongated susceptor elements during or after crimping may facilitate the alignment of elongated susceptor elements, or even provide pre-alignment of elongated susceptor elements, particularly when the sheet material is corrugated and deposited on the main surface of the sheet material during or after crimping, so that the elongated susceptor elements can be positioned within the corrugations created during crimping.

[0042] As described above, the geometric shape of the elongated susceptor element, particularly its relative dimensions, significantly affects the heating efficiency and, consequently, the substrate extraction efficiency. Therefore, the elongated susceptor element may be selected such that the ratio of the length dimension to the maximum cross-sectional dimension is greater than 4, particularly greater than 10, preferably greater than 20, more preferably greater than 25, even more preferably greater than 30, and most preferably greater than 35. As used herein, the term “maximum cross-sectional dimension” refers to the maximum dimension of the elongated susceptor element perpendicular to the principal dimension (length dimension). This ratio may also be expressed as an aspect ratio or morphological factor.

[0043] As used herein, the ratio of the maximum length dimension of an elongated susceptor element to the maximum cross-sectional dimension of an elongated susceptor element perpendicular to the length dimension is also expressed as a morphological factor or aspect ratio. Therefore, the morphological factor of an elongated susceptor element is greater than 4, particularly greater than 10, preferably greater than 20, more preferably greater than 25, even more preferably greater than 30, and most preferably greater than 35.

[0044] The ratio of the maximum length dimension to the maximum cross-sectional dimension (morphological factor) preferably has both a lower and upper limit. Therefore, the ratio of the maximum length dimension of an elongated susceptor element to the maximum cross-sectional dimension perpendicular to the (maximum) length dimension, i.e., the morphological factor of an elongated susceptor element, may be in the range of 4 to 500, particularly 10 to 300, preferably 20 to 200, and more preferably 30 to 100.

[0045] In absolute terms, the length dimension of the elongated susceptor element may be in the range of 20 micrometers to 50 millimeters, particularly 100 micrometers to 16 millimeters, preferably 0.5 millimeters to 5 millimeters. Such maximum length dimensions are advantageous with respect to alignment according to this disclosure.

[0046] Depending on the absolute value of each of the maximum length dimensions, it is preferable that the absolute value of each of the maximum cross-sectional dimensions of the elongated susceptor element be selected to be advantageously within the preferred range defined above, such that the morphological factor exceeds the lower limit defined above. Therefore, the maximum cross-sectional dimension of the elongated susceptor element may be in the range of 5 micrometers to 500 micrometers, particularly 10 micrometers to 150 micrometers, preferably 80 micrometers to 120 micrometers. In particular, the maximum cross-sectional dimension of the elongated susceptor element may be 500 micrometers or less, particularly 100 micrometers, preferably 50 micrometers, and more preferably 25 micrometers.

[0047] The heating efficiency also depends on the density of elongated susceptor elements in the aerosol-forming substrate. Higher densities result in greater heating efficiency. The (volume) density of elongated susceptor elements in the aerosol-forming substrate is preferably in the range of 0.001 susceptor elements per cubic millimeter to 30 susceptor elements per cubic millimeter, and more particularly in the range of 0.1 susceptor elements per cubic millimeter to 10 susceptor elements per cubic millimeter. Similarly, the mass density of elongated susceptor elements in the aerosol-forming substrate may be in the range of 0.002 milligrams of susceptor mass per cubic millimeter to 0.3 milligrams of susceptor mass per cubic millimeter, and more particularly in the range of 0.01 milligrams of susceptor mass per cubic millimeter to 0.1 milligrams of susceptor mass per cubic millimeter.

[0048] In general, a susceptor element may have any geometric shape as long as it is elongated. In particular, an elongated susceptor element may have either a cylindrical shape or an elongated ellipse shape. That is, an elongated susceptor element may have a rod-like shape or a particle-like shape.

[0049] As an example, the elongated susceptor element may be a fibrous element, particularly a chopped fiber element or a milled fiber element. In another embodiment, the elongated susceptor element may be a wire element, or a thread element, or a particle element, or a rod element. Advantageously, the fibrous element, or wire element, or thread element, or particle element, or filament element, or rod element can be made from inductively heatable materials such as metal fibers, or metal wires, or metal threads, and are readily available at low cost.

[0050] As seen in a plane perpendicular to the length dimension of the elongated susceptor element, the cross-section of the elongated susceptor element may have the shape of a circle, oval, ellipse, triangle, rectangle, quadrilateral, or polygon. If the cross-section is circular, the above-mentioned maximum cross-sectional dimension of the elongated susceptor element corresponds to the diameter of the susceptor element that is maximum along the length dimension of the elongated susceptor element. If the cross-section is elliptical or oval, the above-mentioned maximum cross-sectional dimension of the susceptor element corresponds to the length of the semi-major axis of the oval or elliptical cross-section that is maximum along the length dimension of the elongated susceptor element. If the cross-section is quadrilateral or generally rectangular, the above-mentioned maximum cross-sectional dimension of the susceptor element corresponds to the length of the edge / major edge of the quadrilateral / rectangular cross-section.

[0051] Generally, as used herein, the term “susceptor element” refers to an element comprising a susceptor material having the ability to convert electromagnetic energy into heat when subjected to an alternating magnetic field. This may be the result of at least one of hysteresis loss and eddy currents induced within the susceptor material, depending on the electrical properties and magnetism of the susceptor material. Hysteresis loss occurs in ferromagnetic or ferrimagnetic susceptor materials due to magnetic domains in the material being switched under the influence of an alternating electromagnetic field. Eddy currents may be induced when the susceptor material is conductive. In the case of a conductive ferromagnetic susceptor or a conductive ferrimagnetic susceptor, heat can be generated due to both eddy currents and hysteresis loss.

[0052] Therefore, elongated susceptor elements may generally be conductive and ferromagnetic or ferrimagnetic, or at least one of the latter. In particular, the susceptor material of an elongated susceptor element may be non-conductive but may be either ferromagnetic or ferrimagnetic. Alternatively, the susceptor material of an elongated susceptor element may be conductive but neither ferromagnetic nor ferrimagnetic.

[0053] Preferably, the susceptor material of the elongated susceptor element includes, or may consist of, a metal, such as ferrite iron, or stainless steel, specifically grade 410, grade 420, or grade 430 stainless steel, or ferrimagnetic ceramic.

[0054] In addition to the susceptor material, the elongated susceptor element may further include a ferromagnetic or ferrimagnetic temperature marker material.

[0055] The susceptor material is optimized with respect to heat loss and therefore heating efficiency, while the temperature marker material is a magnetic (ferromagnetic or ferrimagnetic) material selected to have a Curie temperature that essentially corresponds to a given temperature point in the heating process.

[0056] The temperature marker material may have a Curie temperature of less than 500°C, preferably 400°C or less, specifically 390°C or less. For example, the temperature marker material for an elongated susceptor element may have a Curie temperature in the range of 180°C to 420°C, specifically 210°C to 380°C, preferably 250°C to 380°C. The temperature marker material is primarily a functional material that provides a temperature marker by its Curie temperature, but it may also contribute to the induction heating process of the susceptor arrangement.

[0057] The temperature marker material of the elongated susceptor element may contain or be made of nickel or a nickel alloy.

[0058] The susceptor element may be formed such that the susceptor material is at least partially, preferably completely, surrounded or covered by the temperature marker material.

[0059] Furthermore, the elongated susceptor element may include an outer protective coating that surrounds the susceptor material and, if present, the temperature marker material. The protective coating preferably makes the elongated susceptor element resistant to external influences, particularly corrosive influences.

[0060] The elongated susceptor elements provided may have substantially identical properties such as susceptor material, maximum dimensions, morphological ratio, temperature marker material, and outer coating. Alternatively, mixtures of elongated susceptor elements having different properties may be provided.

[0061] Furthermore, the susceptor material of the susceptor element itself may also have a temperature marker function. That is, an elongated susceptor element may contain a single material that acts as both the susceptor material and the temperature marker material.

[0062] Another aspect of this disclosure provides a method for manufacturing an aerosol-generating segment for use in an induction-heatable aerosol-generating article. The method for manufacturing an aerosol-generating segment includes aligning elongated susceptor elements in or on an aerosol-forming substrate, as described herein. A sheet material is assembled into a rod downstream of a magnetic alignment device. The rod is cut into segments, each segment comprising a plurality of susceptor elements.

[0063] Multiple susceptor elements may include, for example, at least 5 susceptor elements, or at least 10 susceptor elements, or at least 20 susceptor elements, or at least 50 susceptor elements.

[0064] The process of gathering the sheet material into the rod may include transporting the sheet material through a molding device. The molding device may have a funnel shape.

[0065] This disclosure also relates to an apparatus for aligning elongated susceptor elements within or on an aerosol-forming substrate. The apparatus may be particularly suitable for use in the method according to this disclosure. Accordingly, the above description applies as appropriate to the apparatus according to this disclosure.

[0066] The apparatus may include a magnetic alignment device configured to generate an aligning magnetic field and apply it to an aerosol-forming substrate containing elongated susceptor elements. The aerosol-forming substrate is provided as a sheet material. When applied to a sheet material containing elongated susceptor elements, the aligning magnetic field pulls the elongated susceptor elements along the aligning magnetic field with respect to a reference axis of the sheet material, at least partially.

[0067] The elongated susceptor elements may preferably be supplied to and delivered to the aerosol-forming substrate via a susceptor supply source upstream of the magnetic alignment device. The susceptor supply source may be a hopper in particular.

[0068] The aerosol-forming substrate in the form of a sheet material may preferably be supplied to or through a magnetic alignment device via a substrate supply. The substrate supply source may preferably be configured to supply the sheet material vertically above the magnetic alignment device.

[0069] The substrate supply source may preferably include a conveyor belt or one or more rollers for supplying the aerosol-forming substrate in the form of a sheet material to and / or through the magnetic alignment device in a conveying direction, either continuously or in stages. The conveying direction may preferably be parallel to a plane defined by the sheet material, or parallel to a plane in contact with the sheet material at the alignment location.

[0070] The magnetic alignment device may include at least one magnetic roller, which may be a permanent magnetic roller or an electromagnetic roller, and may include one or more permanent magnets and / or one or more electromagnets.

[0071] In a preferred configuration, the magnetic roller may include a plurality of permanent magnets arranged circumferentially around the axis of rotation of the magnetic roller within the periphery of the magnetic roller, and / or a plurality of electromagnets arranged circumferentially around the axis of rotation of the magnetic roller within the periphery of the magnetic roller.

[0072] The magnetic field outside the magnetic roller may preferably extend at least circumferentially around the magnetic roller. Alternatively, the magnetic field outside the magnetic roller may extend at least partially parallel to the axis of rotation of the magnetic roller.

[0073] As used herein, the term “aerosol-generating article” means an article comprising at least one aerosol-forming substrate having the ability to release volatile compounds when heated to form an aerosol. An aerosol-generating article may be a consumable, in particular a consumable that is discarded after a single use. For example, an article may be an elongated or rod-shaped article. An elongated or rod-shaped article may have a shape similar to that of a conventional cigarette. Specifically, such articles may have a circular, elliptical, oblong, square, rectangular, triangular, or polygonal cross-section.

[0074] As used herein, the term “aerosol-forming substrate” means a substrate formed from or containing an aerosol-forming material having the ability to release volatile compounds upon heating in order to generate aerosols. Aerosol-forming substrates are preferably intended to be heated rather than burned in order to release aerosol-forming volatile compounds. Therefore, such substrates may be referred to as heat-non-combustible aerosol-forming substrates. Similarly, aerosol-generating articles containing such aerosol-forming substrates may be referred to as heat-non-combustible aerosol-generating articles.

[0075] Generally, an aerosol-forming substrate may comprise at least one aerosol-forming material and at least one sensory material, both of which are volatile when heated. The sensory material may comprise at least one of a tobacco-containing material, a nicotine-containing material, and a flavoring substance. Examples of suitable aerosol-forming materials are glycerin and propylene glycol. Examples of flavoring substances may include plant extracts and natural or artificial flavors.

[0076] The aerosol-forming substrate may be a solid aerosol-forming substrate, a gel-like aerosol-forming substrate, or any combination thereof.

[0077] As described above, the aerosol-forming substrate may contain tobacco-containing material that contains volatile tobacco-flavored compounds released from the substrate upon heating. Specifically, the aerosol-forming substrate may contain reconstituted tobacco material or tobacco-containing slurry. Therefore, the aerosol-generating article may be a tobacco-containing article. Alternatively, or additionally, the aerosol-forming substrate may contain non-tobacco material. The aerosol-forming substrate may also contain other additives and components (such as nicotine or flavoring agents).

[0078] The aerosol-forming substrate may also be a paste-like material, a sachet of a porous material containing the aerosol-forming substrate, or loose tobacco mixed with, for example, a gelling agent or adhesive, which may contain a common aerosol-forming agent such as glycerin, and which is compressed or molded into a plug.

[0079] Aerosol-forming substrates are made from sheet materials. For example, an aerosol-forming substrate may be made from a crimped tobacco sheet containing tobacco material, organic fibers, a binder, and an aerosol-forming element. Alternatively, an aerosol-forming substrate may be made from a sheet material containing nicotine-containing material, organic fibers, a binder, and an aerosol-forming element. As yet another alternative, an aerosol-forming substrate may be made from a sheet material containing tobacco cut filler. In this regard, aerosol-generating articles have been found to be easy to manufacture, particularly with respect to the preferred alignment of elongated susceptor elements with respect to a predefined reference axis of the article, when applied to and aligned with an aerosol-forming substrate when the elongated susceptor elements are in the form of a sheet material. This may be a result of a manufacturing process that includes the deposition of elongated susceptor elements onto the outer surface of the sheet material and / or the dispersion of elongated susceptor elements within the sheet material, either during the primary process in which the sheet material is manufactured, or when elongated susceptor elements are deposited on the main surface of the sheet material, or during the secondary process in which the sheet material is machined and combined with other semi-finished products to obtain a final product. As a result, the elongated susceptor elements may ultimately be positioned on the outer surface of the sheet material, aligned with each other and at least partially aligned with the reference axis of the sheet material, at least partially embedded in the sheet material near the outer surface of the sheet material, or dispersed throughout the sheet material. This can also be observed when the sheet material is subsequently machined, for example, when it is crimped and assembled to form a substrate plug within the final article. [Brief explanation of the drawing]

[0080] [Figure 1A] Figure 1A schematically shows a magnetic alignment device according to the present invention in a top view. [Figure 1B] Figure 1B schematically shows the details of the aligned, elongated susceptor elements. [Figure 1C] Figure 1C schematically shows details of partially aligned, elongated susceptor elements. [Figure 2A] Figure 2A schematically shows a magnetic alignment device according to one embodiment of the present invention in a top view. [Figure 2B] Figure 2B schematically shows the details of the aligned, elongated susceptor elements. [Figure 2C] Figure 2C schematically shows details of partially aligned, elongated susceptor elements. [Figure 3] Figure 3 schematically shows a magnetic alignment device according to the present invention in a side view. [Figure 4] Figure 4 schematically shows the details of the magnetic roller according to the present invention. [Figure 5] Figure 5 schematically shows a flowchart of the method according to the present invention. [Figure 6] Figure 6 shows a schematic and detailed representation of the substrate element, including the elongated susceptor element. [Figure 7] Figure 7 schematically illustrates the manufacturing process of a substrate element or segment. [Modes for carrying out the invention]

[0081] The present invention is defined in the claims. However, a non-exclusive list of non-limiting embodiments is provided below. One or more features of these embodiments may be combined with one or more features of any of the features described above, for example, one or more features of other embodiments, forms, or aspects described herein.

[0082] Example 1: A method for aligning elongated susceptor elements in or on an aerosol-forming substrate for use in an induction-heatable aerosol-generating article, the method comprising: providing an aerosol-forming substrate in the form of a sheet material, wherein the aerosol-forming substrate comprises a plurality of elongated susceptor elements; arranging the sheet material near a magnetic alignment device; and applying an alignment magnetic field to the aerosol-forming substrate using the magnetic alignment device, wherein the alignment magnetic field attracts and aligns the elongated susceptor elements along the alignment magnetic field with respect to a reference axis of the sheet material.

[0083] Example 2: The method according to Example 1, wherein elongated susceptor elements are deposited on the main surface of the sheet material.

[0084] Example 3: The method according to Example 1 or 2, wherein the adhesive is applied to the main surface of the sheet material before the elongated susceptor elements are deposited thereon, or after the elongated susceptor elements are at least partially aligned.

[0085] Example 4: The method according to Example 3, wherein the adhesive contains glycerol.

[0086] Example 5: The method according to Example 1, wherein elongated susceptor elements are dispersed throughout an aerosol-forming substrate provided as a sheet material.

[0087] Example 6: The method according to any one of Examples 1 to 5, wherein the elongated susceptor elements are at least partially aligned such that the angle between the length dimension of the elongated susceptor elements and the reference axis is in the range of +30 degrees to -30 degrees, preferably +25 degrees to -25 degrees, and particularly +10 degrees to -10 degrees.

[0088] Example 7: The method according to any one of Examples 1 to 6, wherein elongated susceptor elements are aligned with respect to each other and substantially parallel to a reference axis.

[0089] Example 8: The method according to any one of Examples 1 to 7, wherein the magnetic alignment device and the sheet material are moved relative to each other during the alignment of elongated susceptor elements.

[0090] Example 9: The method according to any one of Examples 1 to 8, wherein, during the alignment of elongated susceptor elements, the sheet material is moved in a transport direction relative to (particularly through) a magnetic alignment device, and the transport direction is preferably parallel to a plane defined by the sheet material or parallel to a plane in contact with the sheet material at the alignment location.

[0091] Example 10: The method according to Example 9, wherein the transport direction is substantially parallel to the reference axis.

[0092] Example 11: The method according to either one of Examples 9 or 10, wherein the sheet material is moved in the transport direction relative to (particularly through) a magnetic alignment device by a base conveyor belt or by one or more rollers.

[0093] Example 12: The method according to any one of Examples 1 to 11, wherein the magnetic alignment device is positioned vertically below the sheet material at the alignment location.

[0094] Example 13: The method according to any one of Examples 1 to 12, wherein the magnetic alignment device includes at least one magnetic roller.

[0095] Example 14: The method according to Example 13, wherein the magnetic roller is a permanent magnetic roller or an electromagnetic roller.

[0096] Example 15: The method according to either one of Examples 13 or 14, wherein the magnetic roller includes one or more permanent magnets and / or one or more electromagnets.

[0097] Example 16: The method according to any one of Examples 13 to 15, wherein the magnetic roller includes a plurality of permanent magnets arranged circumferentially around the axis of rotation of the magnetic roller within the periphery of the magnetic roller.

[0098] Example 17: The method according to any one of Examples 13 to 16, wherein the magnetic roller includes a plurality of electromagnets arranged circumferentially around the axis of rotation of the magnetic roller within the periphery of the magnetic roller.

[0099] Example 18: The method according to any one of Examples 13 to 17, wherein the magnetic field outside the magnetic roller extends at least partially circumferentially around the magnetic roller.

[0100] Example 19: The method according to any one of Examples 13 to 18, wherein the magnetic field outside the magnetic roller extends at least partially parallel to the axis of rotation of the magnetic roller.

[0101] Example 20: The method according to any one of Examples 1 to 19, wherein the lateral dimension of the conveyor belt substantially corresponds to the lateral dimension of the sheet material.

[0102] Example 21: The method according to any one of Examples 1 to 20, wherein the aerosol-forming substrate is prepared from a substrate slurry cast in the form of a sheet material.

[0103] Example 22: The method according to Example 21, wherein elongated susceptor elements are deposited on the main surface of the sheet material or dispersed throughout the sheet material before the cast substrate slurry dries.

[0104] Example 23: The method according to any one of Examples 1 to 22, wherein the aerosol-forming substrate in the form of a sheet material is a continuous substrate sheet.

[0105] Example 24: The method according to Example 24, wherein the elongated susceptor elements are at least partially aligned during or after crimping a continuous substrate sheet, particularly in the longitudinal direction of the continuous substrate sheet, and particularly in the mechanical direction of the continuous substrate sheet.

[0106] Example 25: The method according to any one of Examples 1 to 24, wherein the ratio of the length dimension to the maximum cross-sectional dimension of the elongated susceptor element is greater than 4, particularly greater than 10, preferably greater than 20, more preferably greater than 25, even more preferably greater than 30, and most preferably greater than 35.

[0107] Example 26: The method according to any one of Examples 1 to 25, wherein the ratio of the length dimension to the maximum cross-sectional dimension of the elongated susceptor element is in the range of 4 to 500, particularly 10 to 300, preferably 20 to 200, and more preferably 30 to 100.

[0108] Example 27: The method according to any one of Examples 1 to 26, wherein the length dimension of the elongated susceptor element is in the range of 20 micrometers to 50 millimeters, particularly 100 micrometers to 16 millimeters, preferably 0.5 millimeters to 5 millimeters.

[0109] Example 28: The method according to any one of Examples 1 to 27, wherein the maximum transverse dimension of the elongated susceptor element is in the range of 5 micrometers to 500 micrometers, particularly 10 micrometers to 150 micrometers, preferably 80 micrometers to 120 micrometers.

[0110] Example 29: The method according to any one of Examples 1 to 28, wherein the maximum transverse dimension of the elongated susceptor element is 500 micrometers or less, particularly 100 micrometers, preferably 50 micrometers, and more preferably 25 micrometers.

[0111] Example 30: The method according to any one of Examples 1 to 29, wherein the elongated susceptor element has either a cylindrical or elongated elliptical shape.

[0112] Example 31: The method according to any one of Examples 1 to 30, wherein the elongated susceptor element is a fibrous element, in particular a chopped fiber element or a milled fiber element, or a wire element, or a thread element, or a particle element or a rod element.

[0113] Example 32: The method according to any one of Examples 1 to 31, wherein the cross-section of the elongated susceptor element in a plane perpendicular to the length dimension of the susceptor element is circular, elliptical, triangular, rectangular, quadrilateral, or polygonal in shape.

[0114] Example 33: The method according to any one of Examples 1 to 32, comprising a susceptor material in which an elongated susceptor element is conductive and at least one of ferromagnetic or ferrimagnetic.

[0115] Example 34: The method according to Example 33, wherein the susceptor material of the elongated susceptor element includes, or consists of, a metal, such as ferrite iron, or stainless steel, specifically grade 410, grade 420, or grade 430 stainless steel, or ferrimagnetic ceramics.

[0116] Example 35: The method according to either Example 33 or 34, wherein the elongated susceptor element further comprises a ferromagnetic or ferrimagnetic temperature marker material in addition to the susceptor material.

[0117] Example 36: The method according to Example 35, wherein the temperature marker material of the elongated susceptor element contains or consists of nickel or a nickel alloy.

[0118] Example 37: In particular, an apparatus for aligning elongated susceptor elements in or on an aerosol-forming substrate for use in any one of Examples 1 to 36, wherein the apparatus comprises a magnetic alignment device configured to apply an alignment magnetic field to an aerosol-forming substrate containing elongated susceptor elements, the aerosol-forming substrate is provided as a sheet material, and the alignment magnetic field pulls the elongated susceptor elements along the alignment magnetic field with respect to a reference axis of the sheet material, thereby aligning them.

[0119] Example 38: The apparatus according to Example 38, further comprising a susceptor supply source configured to provide and supply elongated susceptor elements to an aerosol-forming substrate upstream of a magnetic alignment device.

[0120] Example 39: The apparatus according to either one of Example 37 or 38, further comprising a substrate supply source for providing an aerosol-forming substrate in the form of a sheet material to or through a magnetic alignment device, particularly vertically above the magnetic alignment device.

[0121] Example 40: The apparatus according to Example 39, wherein the substrate supply source includes one or more rollers for supplying an aerosol-forming substrate in the form of a sheet material to or through the magnetic alignment device in the transport direction.

[0122] Example 41: The apparatus according to any one of Examples 37 to 40, wherein the magnetic alignment device includes at least one magnetic roller.

[0123] Example 42: The apparatus according to any one of Examples 37 to 41, wherein the magnetic roller is a permanent magnetic roller or an electromagnetic roller.

[0124] Example 43: The apparatus according to any one of Examples 37 to 42, wherein the magnetic roller includes one or more permanent magnets and / or one or more electromagnets.

[0125] Example 44: The apparatus according to any one of Examples 37 to 43, wherein the magnetic roller includes a plurality of permanent magnets arranged circumferentially around the axis of rotation of the magnetic roller within the periphery of the magnetic roller.

[0126] Example 45: The apparatus according to any one of Examples 37 to 44, wherein the magnetic roller includes a plurality of electromagnets arranged circumferentially around the axis of rotation of the magnetic roller within the periphery of the magnetic roller.

[0127] Example 46: The apparatus according to any one of Examples 37 to 45, wherein the magnetic field outside the magnetic roller extends at least partially circumferentially around the magnetic roller, or the magnetic field outside the magnetic roller extends at least partially parallel to the axis of rotation of the magnetic roller.

[0128] Example 47: A method for manufacturing an aerosol generating segment for use in an induction-heatable aerosol generating article, comprising the method according to any one of Examples 1 to 36, and comprising assembling a sheet material onto a rod downstream of a magnetic alignment device, and cutting the rod into segments, each segment comprising a plurality of susceptor elements.

[0129] Here, we will further describe the examples with reference to the figures.

[0130] All examples shown in the figures are schematic and not to exact scale.

[0131] Figure 1A schematically shows an embodiment of the magnetic alignment device 1 in a top view. A susceptor supply source 2 is located upstream of the magnetic alignment device, which includes magnetic rollers 5, to supply elongated susceptor elements 3 to an aerosol-forming substrate provided as a sheet material 4. The magnetic rollers 5 are located vertically below the sheet material 4, and in the case of the top view in Figure 1A, below the plane of the sheet material 4. For clarity, in the embodiment shown in Figure 1A, the elongated susceptor elements 3 are shown as being deposited on the main surface of the sheet material 4, but according to other possible embodiments, the elongated susceptor elements 3 may be dispersed throughout the aerosol-forming substrate provided as the sheet material 4. The sheet material 4 is transported by the susceptor supply source in a transport direction C, which will be described in more detail later. The magnetic rollers 5 are configured to generate an aligning magnetic field that aligns the elongated susceptor elements 3, to which an aligning magnetic field is applied, along the aligning magnetic field. In the embodiment shown in Figure 1A, the elongated susceptor elements 3 are transported from left to right along the transport direction C. Therefore, the elongated susceptor elements 3 on the right side of Figure 1A are aligned substantially parallel to each other compared to the elongated susceptor elements 3 on the left side of Figure 1A. The magnetic alignment device 1 may be configured such that the sheet material 4 is conveyed in stages and an alignment magnetic field is intermittently generated by the magnetic rollers 5. In this case, the elongated susceptor elements 3 are conveyed to the alignment location and an alignment magnetic field is applied to the elongated susceptor elements 3 to align them. The alignment magnetic field 5 is then turned off and the sheet material 4 is further conveyed in the conveying direction C until the next unaligned portion of the elongated susceptor elements 3 is placed in the alignment location, and the process is repeated. However, it is preferable that the magnetic alignment device 1 is configured such that the sheet material 4, which is a continuous substrate sheet, is conveyed continuously in the conveying direction C by passing through the magnetic rollers 5, where the elongated susceptor elements 3 are aligned by the alignment magnetic field generated by the magnetic rollers 5. The alignment magnetic field generated by the magnetic roller 5 extends at least partially circumferentially around the magnetic roller 5 in the embodiment shown in Figure 1A, and the elongated susceptor element 3 is aligned substantially parallel to the reference axis R of the sheet material 4, and the reference axis R is parallel to the transport direction C, as shown in detail in Figure 1B.In this case, the elongated susceptor element 3 may also be aligned substantially parallel to the projection of the transport direction C onto the plane that is in contact with the sheet material 4 at the alignment location.

[0132] Alternatively, as shown in detail in Figure 1C, the elongated susceptor element 3 may be aligned with at least partial alignment, and the angle alpha (α) between the length dimension of the elongated susceptor element 3 and the reference axis R parallel to the transport direction C is in the range of +30° to -30°, particularly +25° to -25°, preferably +10° to -10°. As a result, the elongated susceptor element 3 can be aligned with at least partial alignment with the projection of the transport direction C onto the plane in contact with the sheet material at the alignment location.

[0133] Figure 2A schematically shows another embodiment of the magnetic alignment device 1 in a top view. The magnetic alignment device 1 shown in Figure 2A substantially corresponds to the magnetic alignment device 1 shown in Figure 1A. A susceptor supply source 2 is located upstream of the magnetic alignment device, which includes magnetic rollers 5, to supply elongated susceptor elements 3 to an aerosol-forming substrate provided as a sheet material 4. The magnetic rollers 5 are located vertically below the sheet material 4, and in the case of the top view in Figure 2A, below the plane of the sheet material 4. For clarity, in the embodiment shown in Figure 2A, the elongated susceptor elements are shown as deposited on the main surface of the sheet material 4, but according to other possible embodiments, the elongated susceptor elements 3 may be dispersed throughout the aerosol-forming substrate provided as the sheet material 4. The sheet material 4 is transported by the susceptor supply source in a transport direction C, which will be described in more detail later. The magnetic rollers 5 are configured to generate an aligning magnetic field that aligns the elongated susceptor elements 3, to which the aligning magnetic field is applied, along the aligning magnetic field. In the embodiment shown in Figure 2A, the elongated susceptor elements 3 are transported from left to right along the transport direction C. Therefore, the elongated susceptor elements 3 on the right side of Figure 2A are substantially parallel to each other compared to the elongated susceptor elements 3 on the left side of Figure 2A. The magnetic alignment device 1 may be configured such that the sheet material 4 is transported in stages and an alignment magnetic field is intermittently generated by the magnetic rollers 5. In this case, the elongated susceptor elements 3 are transported to an alignment location, and an alignment magnetic field is applied to the elongated susceptor elements 3 to align them. The alignment magnetic field 5 is then turned off, and the sheet material 4 is further transported in the transport direction C until the next portion of the unaligned elongated susceptor elements 3 is placed in the alignment location, and the process is repeated. However, it is preferable that the magnetic alignment device 1 is configured such that the sheet material 4, which is a continuous substrate sheet, is transported continuously in the transport direction C by passing through the magnetic rollers 5, where the elongated susceptor elements 3 are aligned by the alignment magnetic field generated by the magnetic rollers 5.The alignment magnetic field generated by the magnetic roller 5 extends at least partially parallel to the axis of rotation of the magnetic roller 5 in the embodiment shown in Figure 2A, and the elongated susceptor elements 3 are aligned with each other and substantially parallel to the reference axis R of the sheet material 4, the reference axis R being perpendicular to the transport direction C, as shown in detail in Figure 2B. In this case, the elongated susceptor elements 3 may also be aligned substantially parallel to the reference axis and perpendicular to the projection of the transport direction C onto the plane tangent to the sheet material 4 at the alignment location.

[0134] Alternatively, as shown in detail in Figure 2C, the elongated susceptor elements 3 may be aligned with at least partial alignment, and the angle alpha (α) between the length dimension of the elongated susceptor elements 3 and the reference axis R perpendicular to the transport direction C is in the range of +30° to -30°, particularly +25° to -25°, preferably +10° to -10°. As a result, the elongated susceptor elements 3 can be aligned at least partially perpendicular to the projection of the transport direction C onto the plane in contact with the sheet material at the alignment location.

[0135] Figure 3 shows a schematic and simplified side view of the magnetic alignment device 1 according to the present invention, which includes the substrate supply source described above. The sheet material 4 is conveyed in a conveying direction C parallel to the plane defined by the sheet material 4. The sheet material 4 may be conveyed in the conveying direction C, either continuously or in stages, by one or more rollers 6 and / or one or more conveyor belts 7. The magnetic rollers 5 are positioned vertically below the sheet material 4 and generate an alignment magnetic field for aligning elongated susceptor elements 3 (not shown) that pass over the magnetic rollers 5, as described above. The magnetic rollers 5 may be permanent magnetic rollers or electromagnetic rollers.

[0136] Figure 4 shows a preferred embodiment of the magnetic roller 5 in more detail. The magnetic roller 5 includes a plurality of magnets 8 arranged circumferentially within the magnetic roller 5 around the axis of rotation of the magnetic roller 5. The magnets 8, which may be electromagnets and / or permanent magnets, may rotate with the magnetic roller 5 or their position may be fixed. Furthermore, the magnets 8 are arranged and configured such that, as shown in Figures 1A and 2A, an alignment magnetic field for at least partially aligning the elongated susceptor element 3 extends at least partially circumferentially around the magnetic roller 5, within at least a portion of the magnetic roller 5 through which the sheet material 4 and therefore the elongated susceptor element 3 pass. The magnets 8 may be arranged along the circumferential direction of the magnetic roller 5, alternatingly having the outermost magnetic north pole N and magnetic south pole S, in order to generate an alignment magnetic field that extends at least partially circumferentially around the magnetic roller 5. Thereafter, the elongated susceptor element 3 is at least partially aligned as it passes through the magnetic roller 5.

[0137] Figure 5 shows a flowchart of the method according to the present invention. The method for aligning elongated susceptor elements in an aerosol-forming substrate can be carried out using a magnetic alignment device 1 according to the present invention, as described above. In a first step 20, the aerosol-forming substrate is provided in the form of a sheet material 4, which includes elongated susceptor elements 3 deposited on the main surface of the sheet material 4 and / or dispersed throughout the aerosol-forming substrate provided as the sheet material 4. In a second step 21, the sheet material 4 containing the elongated susceptor elements 3 is placed near a magnetic alignment device which may include magnetic rollers 5. In a third step 22, an alignment magnetic field is applied to the aerosol-forming substrate by the magnetic alignment device. The alignment magnetic field pulls the elongated susceptor elements 3 along the alignment magnetic field, at least partially, with respect to the reference axis R of the sheet material 4, thereby aligning them.

[0138] Figure 6 shows a perspective view of a portion of a substrate element 110 or segment 110 that forms part of a rod-shaped aerosol generating article, including a detailed view (lower right) of its internal structure, particularly the structure of the aerosol-forming substrate and the elongated susceptor element 3. As can be seen from both the perspective view and the detailed view, the aerosol-forming substrate is made from a sheet material 4 assembled into the cylindrical shape of the substrate element 110 after the elongated susceptor element 3 has been aligned. For example, the aerosol-forming substrate 4 may be made from a crimped tobacco sheet containing tobacco material, organic fibers, a binder, and aerosol. As can be seen further from the detailed view, at least a portion of the elongated susceptor element 3 is still observable even after the sheet material 4 has been crimped and assembled. This may be the result of a manufacturing process that, according to the present invention, includes the deposition of elongated susceptor elements 3 onto the main surface of the sheet material 4, and at least partial alignment and / or dispersion of the elongated susceptor elements 3 through an aerosol-forming substrate provided as a subsequent sheet material 4, as well as at least partial alignment of the elongated susceptor elements 3 either during a primary process in which the subsequent sheet material 4 is produced, or during a secondary process in which the sheet material 4 is machined. All elongated susceptor elements 3 within the substrate element 110 are aligned along their length dimension (main dimension) substantially parallel to a predetermined reference axis of the aerosol-generating article (corresponding to the reference axis R of the sheet material), where the length axis 101 of the article is selected to coincide with the orientation M of the magnetic field lines of an alternating magnetic field used to inductively heat the elongated susceptor elements 3 when, for example, the aerosol-generating article engages with an aerosol generator that provides an alternating magnetic field. As mentioned above, the heating efficiency is maximized when all the elongated susceptor elements 3 are aligned parallel to the direction M of the alternating magnetic field.

[0139] Figure 7 schematically illustrates the manufacturing of a base element or segment 110. Downstream of the magnetic alignment device 1, the sheet material 4 is conveyed through a funnel-shaped molding device 120, thereby assembling the sheet material 4 into a rod 130. Downstream of the molding device 120, a cutting device 140 cuts the rod 130 into base elements or segments 110. Each base element or segment 110 contains multiple susceptor elements 3.

[0140] For the purposes of this specification and the appended claims, unless otherwise indicated, all numbers representing amounts, quantities, percentages, etc., are understood to be modified in all cases by the term “approximately.” Furthermore, all ranges include the disclosed maximum and minimum values, as well as any intermediate ranges contained within them, whether or not they are specifically enumerated herein. Thus, in this context, numerical value A is understood as A ± 5% of A. In this context, numerical value A may be considered to include numerical values ​​that fall within the general standard error range for the measurement of the characteristic that numerical value A modifies. In some examples used in the appended claims, numerical value A may deviate by the percentages enumerated above, as long as the amount of deviation from A does not substantially affect the basic and novel characteristics of the invention described in the claims. Furthermore, all ranges include the disclosed maximum and minimum values, as well as any intermediate ranges contained within them, whether or not they are specifically enumerated herein.

Claims

1. A method for aligning elongated susceptor elements in or on an aerosol-forming substrate for use in an induction-heatable aerosol-generating article, wherein the method is - A step of providing an aerosol-forming substrate in the form of a sheet material, wherein the aerosol-forming substrate includes a plurality of elongated susceptor elements. - A step of arranging the sheet material near the magnetic alignment device, A method comprising the step of applying an alignment magnetic field to the aerosol-forming substrate using the magnetic alignment device, wherein the alignment magnetic field pulls the elongated susceptor element at least partially along the alignment magnetic field with respect to a reference axis of the sheet material, thereby aligning it.

2. The method according to claim 1, wherein the elongated susceptor elements are deposited on the main surface of the sheet material.

3. The method according to claim 1, wherein the elongated susceptor elements are dispersed throughout the aerosol-forming substrate provided as a sheet material.

4. The method according to any one of claims 1 to 3, further comprising providing the aerosol-forming substrate, which includes the plurality of elongated susceptor elements, to or through the magnetic alignment device.

5. The method according to any one of claims 1 to 4, further comprising transporting the aerosol-forming substrate, which includes the plurality of elongated susceptor elements, to the magnetic alignment device.

6. The method according to any one of claims 1 to 5, further comprising supplying the elongated susceptor element to the aerosol-forming substrate upstream of the magnetic alignment device.

7. The method according to any one of claims 1 to 6, wherein the elongated susceptor elements are at least partially aligned such that the angle between the length dimension of the elongated susceptor elements and the reference axis is in the range of +30 degrees to -30 degrees, preferably +25 degrees to -25 degrees, and particularly +10 degrees to -10 degrees.

8. The method according to any one of claims 1 to 7, wherein the elongated susceptor elements are aligned with respect to each other and substantially parallel to the reference axis.

9. The method according to any one of claims 1 to 8, wherein the sheet material is moved in the transport direction relative to the magnetic alignment device while the elongated susceptor elements are being aligned.

10. The method according to any one of claims 1 to 8, wherein, during the alignment of the elongated susceptor elements, the sheet material is moved in the transport direction through the magnetic alignment device.

11. The method according to claim 9 or 10, wherein the conveying direction is parallel to a plane defined by the sheet material, or parallel to a plane in contact with the sheet material at the alignment location.

12. The method according to any one of claims 9 to 11, wherein the transport direction is substantially parallel to the reference axis.

13. The method according to any one of claims 1 to 12, wherein the magnetic alignment device is disposed vertically below the sheet material at the alignment location.

14. The method according to any one of claims 1 to 13, wherein the magnetic alignment device includes at least one magnetic roller.

15. The method according to claim 14, wherein the magnetic field outside the magnetic roller extends at least partially in a circumferential direction around the magnetic roller.

16. The method according to any one of claims 14 or 15, wherein the magnetic field outside the magnetic roller extends at least partially parallel to the axis of rotation of the magnetic roller.

17. The method according to any one of claims 1 to 16, wherein the aerosol-forming substrate is made from a substrate slurry cast in the form of the sheet material.

18. The method according to claim 17, wherein the elongated susceptor elements are deposited on the main surface of the sheet material or dispersed throughout the sheet material before the cast substrate slurry is dried.

19. The method according to any one of claims 1 to 18, wherein the ratio of the length dimension to the maximum cross-sectional dimension of the elongated susceptor element is greater than 4, particularly greater than 10, preferably greater than 20, more preferably greater than 25, even more preferably greater than 30, and most preferably greater than 35.

20. A method for manufacturing an aerosol generating segment for use in an induction-heatable aerosol generating article, wherein the method is - The method according to any one of claims 1 to 19, - A step of gathering the sheet material into the rod downstream of the magnetic alignment device, - A method comprising the step of cutting the rod into segments, wherein each segment includes a plurality of susceptor elements.

21. In particular, an apparatus for aligning elongated susceptor elements in or on an aerosol-forming substrate, for use in the method according to any one of claims 1 to 20, wherein the apparatus is Magnetic alignment device and A substrate supply source for supplying an aerosol-forming substrate in the form of a sheet material to or through a magnetic alignment device, wherein the aerosol-forming substrate comprises an elongated susceptor element, The magnetic alignment device is configured to apply an alignment magnetic field to the aerosol-forming substrate including the elongated susceptor element, wherein the alignment magnetic field pulls the elongated susceptor element towards the alignment magnetic field, at least partially, with respect to the reference axis of the sheet material, thereby aligning it.

22. The apparatus according to claim 21, further comprising a susceptor supply source configured to provide and supply the elongated susceptor elements to the aerosol-forming substrate upstream of the magnetic alignment device.

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