Device including a dielectric layer connected to an anisotropic layer

Abstract

The device includes an outer adhesive layer containing a conductive gel or a conductive adhesive, at least one layer of an anisotropic material, a layer of a dielectric material, and a skin contact layer containing a conductive gel or a conductive adhesive. The at least one layer of an anisotropic material and the layer of a dielectric material are disposed between the outer adhesive layer and the skin contact layer. The layer of a dielectric material contacts at least a first layer of the at least one layer of an anisotropic material to form a capacitive structure.

Description

Technical Field

[0001] [Cross - Reference to Related Applications] This application claims priority to and the benefit of the filing date of U.S. Provisional Patent Application No. 63 / 356,228, filed on June 28, 2022, the entire disclosure of which is incorporated herein by reference.

[0002] This application relates to an apparatus for providing a tumor treatment field, the apparatus including at least one layer of anisotropic material and a layer of dielectric material in contact with the anisotropic material.

Background Art

[0003] Tumor Treating Fields (TTFields) therapy is a proven approach for treating tumors using alternating electric fields at frequencies in the range of 50 kHz to 1 MHz, more typically 100 - 500 kHz. The alternating electric fields are induced by an electrode assembly (e.g., an array of capacitive electrodes, also referred to as a transducer array) placed on the opposite side of the target location within the subject's body. When an alternating voltage is applied between the opposing electrode assemblies, an alternating current flows through the electrode assemblies and into the subject's body.

Summary of the Invention

Means for Solving the Problems

[0004] In one aspect, the apparatus disclosed herein includes an outer adhesive layer including a conductive gel or conductive adhesive, at least one layer of anisotropic material, a layer of dielectric material, and a skin - contact layer including a conductive gel or conductive adhesive. The at least one layer of anisotropic material and the layer of dielectric material are disposed between the outer adhesive layer and the skin - contact layer. The layer of dielectric material contacts at least a first layer of the at least one layer of anisotropic material to form a capacitive structure.

Brief Description of the Drawings

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DETAILED DESCRIPTION OF THE INVENTION

[0006] Hereinafter, various embodiments will be described in detail with reference to the accompanying drawings, where the same reference numerals represent the same elements.

[0007] This application describes, for example, a device (e.g., an exemplary treatment assembly) that can be used to deliver a TT field to a subject's body and treat one or more cancers or tumors located in the subject's body.

[0008] The present invention can be more easily understood by referring to the following detailed description, examples, drawings, claims, and the descriptions before and after them. However, it should be understood that the present invention is not limited to the specific devices, apparatuses, systems, and / or methods disclosed, and can of course be modified, unless otherwise specified.

[0009] The headings are provided for convenience only and should not be construed as limiting the invention in any way. Embodiments shown in any heading or any part of this disclosure can be combined with embodiments shown in the same or any other heading or other part of this disclosure.

[0010] Every combination of elements described in this specification is included in the present invention in all its possible variations, unless otherwise indicated herein or clearly inconsistent with the context.

[0011] First Figure 1 shows a conventional device for applying a TT field. As shown, the device may include a circuit board, a metal pad connected to the circuit board, a ceramic disk below the metal pad that functions as a dielectric material, and a skin contact layer that includes a hydrogel.

[0012] In the devices, systems, and methods disclosed herein, by using a polymer film as a layer of dielectric material, higher flexibility and thus better conformity with the subject's skin are expected compared to conventional ceramic disks. However, high dielectric constant polymer films are fragile and may often have holes when adjacent to metal pads and during the cutting process in array manufacturing. Furthermore, high dielectric constant polymers are expensive, and less expensive materials are needed. The devices, systems, and methods disclosed herein provide a level of protection for the layer of dielectric material. Further, when providing the disclosed devices, systems, and methods in which the dielectric material is connected to one or more layers of anisotropic material, the contact area with the capacitive layer can be the entire area of the one or more layers of anisotropic material. By increasing the area of the capacitor, the dielectric material does not need to have such a high dielectric constant, so less expensive materials can be used (for example, less expensive polymers or metal oxides such as Al2O3 that can be applied to a substrate by chemical vapor deposition (CVD) and have sufficient flexibility as a thin film).

[0013] Device Referring to FIGS. 2 to 5, an apparatus 10 including an outer adhesive layer 20 is disclosed herein. The outer adhesive layer 20 may include a conductive gel or a conductive adhesive 22. The apparatus 10 may further include at least one layer 30 of an anisotropic material, a layer 40 of a dielectric material, and a skin contact layer 50. The skin contact layer 50 may include a conductive gel or a conductive adhesive 52. In some embodiments, the layer of anisotropic material is a layer of a non-metallic anisotropic material.

[0014] The at least one layer 30 of anisotropic material and the layer 40 of dielectric material can be disposed between the outer adhesive layer 20 and the skin contact layer 50. The layer 40 of dielectric material can contact at least a first layer 30a of the at least one layer 30 of anisotropic material to form a capacitive structure 12.

[0015] In some embodiments, the apparatus 10 may include a circuit board 60 (e.g., a printed circuit board (PCB) or a flexible circuit). The circuit board 60 can be electrically connected to the outer adhesive layer 20. In some optional embodiments, the circuit board 60 can be electrically connected to the outer adhesive layer 20 via one or more conductive elements (e.g., metal pads 70) that are in electrical contact with the circuit board 60. In FIG. 2, two metal elements 70 are shown, but additional electrode elements may be included in the apparatus 10. In an alternative embodiment, the apparatus 10 includes only a single electrode element (e.g., a single metal pad 70).

[0016] In some optional embodiments, the surface areas of the layer 40 of dielectric material and the first layer 30a of the layer of anisotropic material may each be larger than the total surface area of at least one metal pad 70. For example, the surface areas of the layer 40 of dielectric material and the first layer 30a of the layer of anisotropic material may each be at least twice (e.g., 3 to 5 times) larger than the total surface area of at least one metal pad.

[0017] In some embodiments, the anisotropic material layer 30 may include a sheet 32 of anisotropic material having a rear surface 34 and a front surface 36 (the front surface facing the subject's skin side). The sheet 32 of anisotropic material has a first thermal conductivity in a direction perpendicular to the front surface 36. In some embodiments, the thermal conductivity of the sheet in a direction parallel to the front surface may be more than twice the first thermal conductivity. In another embodiment, the sheet 32 of anisotropic material may have a first resistance in a direction perpendicular to the front surface, and the resistance of the sheet in a direction parallel to the front surface may be less than half of the first resistance.

[0018] In some optional embodiments, the first layer 30a of anisotropic material may include graphite.

[0019] Optionally, the first layer 30a of anisotropic material may include synthetic graphite.

[0020] In yet another optional embodiment, the first layer 30a of anisotropic material may include pyrolytic graphite or a graphitized polymer film.

[0021] In yet another optional embodiment, the first layer 30a of anisotropic material may include graphite foil. For example, optionally, the first layer of anisotropic material may include graphite foil made from compressed high-purity exfoliated mineral graphite.

[0022] The dielectric material layer 40 has a skin-facing surface 42 and an opposite outer-facing surface 44. The first layer 30a of anisotropic material has a skin-facing surface 38a and an opposite outer-facing surface 39a.

[0023] In some embodiments, as shown in FIG. 3, the outer-facing surface 44 of the dielectric material layer 40 can contact the skin-facing surface 38a of the first layer 30a of anisotropic material. In some embodiments, as shown in FIG. 3, the outer-facing surface 39a of the first layer 30a of anisotropic material can contact the outer adhesive layer 20. In another embodiment, as shown in FIG. 3, the skin-facing surface 42 of the dielectric material layer 40 can contact the skin contact layer 50.

[0024] In some embodiments, as shown in FIG. 3, the skin-facing surface 42 of the dielectric material layer 40 can contact the outer-facing surface 39a of the first layer 30a of anisotropic material to form the capacitive structure 12. In some optional embodiments, the outer-facing surface 44 of the dielectric material layer 40 can contact the outer adhesive layer 20 (e.g., conductive gel or conductive adhesive 22). In some embodiments, the skin-facing surface 38a of the first layer 30a of anisotropic material can contact the skin contact layer 50. The embodiment of FIG. 4 shows that, compared with the embodiment of FIG. 3, the relative positions of the anisotropic material layer 30a and the dielectric material layer 40 are reversed between the outer adhesive layer 20 and the skin contact layer 50. In some of the embodiments of FIG. 4, the relative positions of other components of the device 10, such as the circuit board 60 and the metal pad 70, may not be changed.

[0025] Referring to FIG. 5, in some optional embodiments, at least one layer 30 of anisotropic material may include a second layer 30b of anisotropic material. The dielectric material layer 40 is located between the first layer 30a and the second layer 30b of anisotropic material to form the capacitive structure 12. The second layer 30b of anisotropic material has a skin-facing surface 38b and an opposite outer-facing surface 39b. In some embodiments, the outer-facing surface 39a of the first layer 30a of anisotropic material can contact the outer adhesive layer 20. In another embodiment, the skin-facing surface 42 of the dielectric material layer 40 can contact the outer-facing surface 39b of the second layer 30b of anisotropic material. In yet another embodiment, the skin-facing surface 38b of the second layer 38b of anisotropic material can contact the skin contact layer 50.

[0026] In some optional embodiments, the dielectric material layer 40 is located between the first layer 30a and the second layer 30b of anisotropic material and can contact both the first layer 30a and the second layer 30b of anisotropic material (FIG. 5). In these embodiments, except for the three-layer sandwich structure (the first layer 30a of anisotropic material - the dielectric material layer 40 - the second layer 30b of anisotropic material), the relative positions of other components of the device 10, such as the circuit board 60 and the metal pad 70, may not be changed.

[0027] Referring to FIG. 6 (and FIGS. 3 - 5 above), in some embodiments, the device may include a wire 80 that is electrically connected to the outer adhesive layer 20. Optionally, in these embodiments, the device 10 does not include a circuit board 60 or a flexible circuit. Optionally, the wire 80 can be connected to the outer adhesive layer 20 via one or more metal pads 70 or metal layers. Optionally, or alternatively, the device 10 does not include a metal pad 70 or a metal layer. Optionally, the wire 80 can be connected to the outer adhesive layer 20 via a circuit board 60 or a flexible circuit. This embodiment can exist for each of the embodiments described herein.

[0028] Referring to FIG. 7, the device 10 may include at least one layer 30 of an anisotropic material and a layer 40 of a dielectric material. The layer 40 of the dielectric material can contact at least a first layer 30a of the at least one layer 30 of the anisotropic material to form a capacitive structure 12.

[0029] The layer 30 of at least one anisotropic material and the layer 40 of dielectric material can be disposed between opposing layers 90 of conductive material (e.g., between the outer adhesive layer 20 and the skin contact layer 50 as shown in FIGS. 3 and 4). In various embodiments, the conductive material layer 90 can optionally include a conductive gel or a conductive adhesive. In another embodiment, the conductive material layer 90 can include a conductive grease. In these embodiments, a cover 92 (e.g., a bandage, a plaster, or other cover structure) can be applied to the patient's skin in a stacked arrangement of the assembly 10. Optionally, a bandage or other cover 92 can be utilized in any of the embodiments described herein. Except for replacing the conductive gel or conductive adhesive of the outer adhesive layer with a conductive grease and optionally adding a bandage or cover 92, the embodiment of FIG. 7 is similar to the embodiment of FIG. 4, and the relative positions of the other components of the device 10, such as the circuit board 60 and the metal pads 70, may not be changed. In fact, replacing the conductive gel or conductive adhesive of the outer adhesive layer with a conductive grease and optionally adding a bandage or cover 92 can be adopted as additional embodiments for any of the other embodiments described herein. Further, replacing the conductive gel or conductive adhesive of the skin contact layer with a conductive grease and optionally adding a bandage or cover 92 can be adopted as additional embodiments for any of the other embodiments described herein.

[0030] In the exemplary embodiments disclosed herein, a sheet of material having anisotropic thermal properties and / or anisotropic electrical properties (also referred to herein as layer 30 of anisotropic material) is incorporated into the device. If the sheet of material has anisotropic thermal properties (e.g., in-plane thermal conductivity is higher than the direction perpendicular to the plane), the sheet spreads heat more uniformly over a larger surface area. If the sheet of material has anisotropic electrical properties (e.g., in-plane thermal conductivity is higher than the direction perpendicular to the plane, or conversely, in-plane resistance is lower than the direction perpendicular to the plane), the sheet spreads current more uniformly over a larger surface area. In either case, when a predetermined alternating voltage is applied to the device, the temperature of the hot spot decreases and the temperature of the cooler region increases. Thus, the current can be increased without exceeding the safety temperature threshold at any point on the subject's skin (thereby increasing the therapeutic effect).

[0031] In some embodiments, the anisotropic material is anisotropic with respect to conductivity properties. In some embodiments, the anisotropic material is anisotropic with respect to thermal conductivity properties. In some embodiments, the anisotropic material is anisotropic with respect to both conductivity properties and thermal conductivity properties.

[0032] The anisotropic thermal properties include directional thermal properties. Specifically, the sheet has a first thermal conductivity in a direction perpendicular to its front surface. Also, the thermal conductivity of the sheet in a direction parallel to the front surface exceeds twice the first thermal conductivity. In some preferred embodiments, the thermal conductivity in the parallel direction exceeds ten times the first thermal conductivity. For example, the thermal conductivity of the sheet in a direction parallel to the front surface can exceed 1.5 times, 2 times, 3 times, 5 times, 10 times, 20 times, 100 times, 200 times, or 1,000 times the first resistance.

[0033] Anisotropic electrical properties include directional electrical properties. Specifically, the sheet has a first resistance in a direction perpendicular to its surface. Further, the resistance of the sheet in a direction parallel to the front surface is lower than the first resistance. In some preferred embodiments, the resistance in the parallel direction is less than half of the first resistance, or less than 10% of the first resistance. For example, the resistance of sheet 70 in a direction parallel to the front surface can be less than 75%, 50%, 40%, 30%, 20%, 10%, 5%, 1%, 0.5%, or 0.1% of the first resistance.

[0034] In some embodiments (e.g., when the sheet of anisotropic material is a sheet of pyrolytic graphite), the sheet of anisotropic material has both anisotropic electrical properties and anisotropic thermal properties.

[0035] In some optional aspects, the layer of anisotropic material is a layer of non-metallic anisotropic material. The use of non-metallic anisotropic materials is particularly advantageous in situations where it is desirable to prevent the movement of ions into the body of a subject. Specifically, when using a metal sheet, there is a possibility that ions may penetrate into the body of the subject.

[0036] In some optional aspects, the dielectric material layer 40 can include a polymer. In an alternative aspect, the dielectric material 40 can be a ceramic material. In an alternative aspect, the dielectric material 40 can be a metal oxide, such as Al2O3, and the metal oxide can be applied to the substrate by chemical vapor deposition (CVD) and has sufficient flexibility as a thin film.

[0037] In various optional aspects, the dielectric material layer 40 can have a dielectric constant in the range of 10 to 50,000.

[0038] In some preferred embodiments, the layer 40 of the dielectric material comprises poly(vinylidene fluoride-trifluoroethylene-chlorotrifluoroethylene) and / or poly(vinylidene fluoride-trifluoroethylene-1-chlorofluoroethylene). These two polymers are abbreviated herein as "poly(VDF-TrFE-CTFE)" and "poly(VDF-TrFE-CFE)", respectively. The dielectric constant of these materials is about 40. In some embodiments, the polymer layer may be poly(vinylidene fluoride-trifluoroethylene-chlorotrifluoroethylene-chlorofluoroethylene) or "poly(VDF-TrFE-CTFE-CFE)".

[0039] In some embodiments, the terpolymers used in the insulating polymer layer may comprise VDF, TrFE, CFE and / or CTFE in any suitable molar ratio. Suitable terpolymers include, for example, those having 30 to 80 mol% of VDF, 5 to 60 mol% of TrFE, with CFE and / or CTFE constituting the remainder of the molar percentage of the terpolymer.

[0040] In all embodiments disclosed herein, it is preferred that the layer of dielectric material completely covers the area of the layer of anisotropic material (or the layer of dielectric material, in combination with one or more other insulating materials, completely covers or substantially completely covers the area of the layer of anisotropic material) so that the two layers function as a capacitive structure. Thus, in an exemplary aspect, the surface area of the layer of dielectric material (or the surface area of the layer of dielectric material in combination with other insulating materials) is greater than or equal to the surface area of the layer of anisotropic material, the dimensions of the layer of anisotropic material are less than or equal to the corresponding dimensions of the layer of dielectric material, and it is contemplated that the periphery of the anisotropic material does not extend beyond the periphery of the dielectric material.

[0041] Although it is preferred to completely cover the anisotropic material, in other embodiments, it is contemplated that the dielectric material may include a configuration that substantially covers the area of the anisotropic material. As used herein, "substantially covers" refers to a configuration in which the dielectric material (or a dielectric material in combination with other insulating materials) covers at least 90% or at least 99% of the surface area of the anisotropic material.

[0042] Method of using the device The method of using the device 10 disclosed herein may include generating an electric field using the device 10. FIG. 6 shows an exemplary system 200 for applying an electric field using the device 10 disclosed herein. A plurality of devices 10 (e.g., two devices as shown) may be arranged with a target region placed therebetween. An alternating voltage or alternating current generator 210 may communicate with each device 10. The alternating voltage or alternating current generator 210 may be configured to generate an alternating electric field in the target region.

[0043] This method may include placing the first device 10 at a first position on or within the subject's body. For example, the device 10 may be placed on the skin on the right side of the subject's head facing the target region (e.g., a brain tumor).

[0044] The second device 10 may be placed at a second position on or within the patient's body. For example, the second device 10 may be placed on the skin of the left side of the subject's head facing the target region.

[0045] An alternating voltage may be applied between the devices 10. The application may be carried out by applying an alternating voltage between (i) a first electrode element (e.g., metal pad 70) disposed in electrical contact with the layer 30 of the anisotropic material of the first device 10 and (ii) a second electrode element disposed in electrical contact with the anisotropic material 30 of the second device 10.

[0046] In some embodiments, the frequency of the alternating voltage is 50 kHz to 1 MHz, or 100 kHz to 500 kHz. In some aspects, the alternating voltage generator can be controlled by a controller. The controller can use the temperature measurement value to control the amplitude of the current supplied through device 10 to maintain the temperature below a safety threshold (e.g., 41 °C). This can be achieved, for example, by measuring the first temperature of the first electrode element, measuring the second temperature of the second electrode element, and controlling the application of the alternating voltage based on the first temperature and the second temperature, as described below.

[0047] More specifically, temperature sensors (e.g., thermistors) can be disposed in thermal contact with the respective electrode elements within each device 10. The temperature sensors can measure the respective first temperature and second temperature (e.g., in the first electrode element and the second electrode element within the first device 10 and the second device 10, respectively), and the controller can control the output of the alternating voltage generator based on these temperatures. By using additional temperature sensors at the positions of additional electrode elements, the temperatures of multiple electrode elements within the transducer array can be measured, and the controller can control the current applied to each electrode element according to the delta temperature compared to the threshold temperature (e.g., 41 °C), thereby balancing the temperature hot spots on the array.

[0048] Effect of the disclosed device The disclosed device 10 can be manufactured more easily and inexpensively compared to other configurations. By using a polymer film as the dielectric material 40, higher flexibility and thus better compatibility with the subject's skin is possible compared to conventional ceramic disks. However, the polymer film is fragile and may often have holes when adjacent to the metal pads 70 and during the cutting process in array manufacturing. The dielectric material 40 can be protected by layers 30 (plural) of anisotropic material, thereby enhancing the durability of the dielectric material 40. Further, when providing a device in which the dielectric material 40 is connected to layers 30 (plural) of anisotropic material, the contact area with the capacitive layer can be the entire area of the layers 30 (plural) of anisotropic material. By increasing the area of the capacitor, the dielectric material does not need to have such a high dielectric constant (polymers with a high dielectric constant are often more expensive than materials with a low dielectric constant), so that a less expensive material can be used (for example, a polymer or a metal oxide such as Al2O3 that can be applied to a substrate by chemical vapor deposition (CVD) and has sufficient flexibility as a thin film).

[0049] Device having a layer containing a conductive adhesive composite Optionally, the outer adhesive layer 20 and / or the skin contact layer 50 may include a hydrogel. It is further contemplated that the conductive adhesive layer 40 and / or the skin contact layer 50 may include a conductive adhesive composite (described further below) rather than a hydrogel.

[0050] In an exemplary aspect, the conductive adhesive composite can include a dielectric material and conductive particles dispersed within the dielectric material. In some embodiments, at least a portion of the conductive particles may define a conductive path through the thickness of the conductive adhesive composite. In some embodiments, it is expected that the conductive particles are arranged in response to the application of an electric field such that the conductive particles are subject to electrophoresis. In some aspects, the dielectric material is a polymeric adhesive. Optionally, in these aspects, the polymeric adhesive can be an acrylic adhesive. In some aspects, the conductive particles can include carbon. Optionally, in these aspects, the conductive particles can include graphite powder. Additionally, or alternatively, the conductive particles can include carbon flakes. Additionally, or alternatively, the conductive particles can include carbon granules. Additionally, or alternatively, the conductive particles can include carbon nanotubes. Additionally, or alternatively, the conductive particles can include carbon black powder. In another aspect, the conductive adhesive composite further includes a polar material (e.g., a polar salt). Examples of polar salts include quaternary ammonium salts such as tetraalkylammonium salts. Exemplary conductive adhesive composites, and methods of manufacturing the same, are disclosed in U.S. Patent No. 8,673,184 and U.S. Patent No. 9,947,432, which are hereby incorporated by reference for all purposes. In an exemplary aspect, the conductive adhesive composite can be a dry carbon / salt adhesive such as the OMNI-WAVE adhesive composition manufactured and sold by FLEXcon (Spencer, Massachusetts, USA). In another exemplary aspect, the conductive adhesive composite can be, for example, the ARcare® 8006 conductive adhesive composition manufactured and sold by Adhesives Research, Inc. (Glen Rock, Pennsylvania, USA).

[0051] In an exemplary aspect, the outer adhesive layer 20 and / or the skin contact layer 50 do not include a hydrogel.

[0052] In another exemplary aspect, the skin contact layer 50 does not include a latex rubber polymer.

[0053] In another exemplary aspect, the skin contact layer 50 does not contain silver or silver chloride.

[0054] In yet another aspect, the conductive adhesive composite layer has a thickness in the range of about 30 μm to about 2000 μm, such as 30 μm to about 200 μm. Optionally, the conductive adhesive composite layer of the outer adhesive layer can have a thickness in the range of about 30 μm to about 2000 μm, about 50 μm to about 1000 μm, about 50 μm to about 200 μm, or about 70 μm to about 150 μm. Optionally, the conductive adhesive composite layer of the skin contact layer can have a thickness in the range of about 30 μm to about 100 μm, about 30 μm to about 70 μm, about 40 μm to about 60 μm, or about 45 μm to about 55 μm.

[0055] In yet another aspect, the conductive adhesive composite does not contain water.

[0056] In an exemplary aspect, the conductive particles of the conductive adhesive composite include multiple groups of conductive particles. In these aspects, the conductive particles of the bonded groups of conductive particles can be aligned to define respective conductive paths through the thickness of the conductor in the adhesive composite electrode assembly.

[0057] Optionally, in an exemplary aspect, the device can further include a release liner covering the skin contact layer. In these aspects, it is contemplated that a release liner can be provided on the device to ensure that the skin contact layer does not adhere to an undesirable surface or location prior to use. Immediately prior to use, the release liner can be removed and the skin contact layer can be placed in contact with the patient's skin.

[0058] In an exemplary aspect, as disclosed herein, it is contemplated that by using a conductive adhesive composite as the skin contact layer, additional backing layers and / or cover layers (e.g., adhesive liners, etc.) can be omitted. In these aspects, the conductive adhesive composite can provide sufficient adhesion to the skin such that no additional layers are needed to maintain the device in the desired position on the subject's body, thereby reducing ease of use and the overall cost associated with manufacturing and use.

[0059] In another aspect, by avoiding the use of hydrogels within the devices disclosed herein, an electrode assembly comprising a conductive adhesive composite as disclosed herein does not require moisture-proof packaging, thereby contemplating that the packaging cost is much more affordable. Further, the conductive adhesive composite of the disclosed electrode assembly can avoid the problem of signal variation of hydrogels, thereby contemplating providing consistent material properties (e.g., stickiness) and reliable performance during the delivery of the TT field. Further, the disclosed conductive adhesive composite has a much longer shelf life than hydrogels, thereby contemplating reducing the frequency with which the electrode assembly (or the skin contact layer of the electrode assembly) has to be replaced.

[0060] Embodiments that include a sheet of anisotropic material are further contemplated to be further useful in avoiding or reducing overheating of the electrodes and the accompanying skin discomfort by dissipating both current and heat laterally (in-plane), rather than concentrating and passing directly through the layers (in a direction perpendicular to the plane of the skin contact layer).

[0061] Exemplary embodiments In view of the described products, systems, and methods and their variations, specific more detailed aspects of the invention are described below. However, these specifically enumerated aspects should not be construed as having a limiting effect on any different claims that include different or more general teachings described herein, nor should the "specific" aspects be construed as being limited in any way other than the literal meaning of the language used.

[0062] Aspect 1: An apparatus comprising an outer adhesive layer comprising a conductive gel or a conductive adhesive, at least one layer of anisotropic material, a layer of dielectric material, and a skin contact layer comprising a conductive gel or a conductive adhesive. The layer of the at least one anisotropic material and the layer of the dielectric material are disposed between the outer adhesive layer and the skin contact layer. The layer of the dielectric material contacts at least a first layer of the layer of the at least one anisotropic material to form a capacitive structure, apparatus.

[0063] Aspect 2: The apparatus according to aspect 1, further comprising a circuit board or a flexible circuit, wherein the circuit board or the flexible circuit is electrically connected to the outer adhesive layer.

[0064] Aspect 3: The apparatus according to aspect 2, wherein the circuit board or the flexible circuit is electrically connected to the outer adhesive layer via at least one metal pad that contacts the circuit board or the flexible circuit.

[0065] Aspect 4: The apparatus according to aspect 3, wherein the surface areas of the layer of the dielectric material and the first layer of the anisotropic material are each larger than the total surface area of the at least one metal pad.

[0066] Aspect 5: The first layer of the anisotropic material includes a sheet of anisotropic material having a front surface and a rear surface, the sheet having a first thermal conductivity in a direction perpendicular to the front surface, and the thermal conductivity of the sheet in a direction parallel to the front surface being more than twice the first thermal conductivity, or the sheet having a first resistance in a direction perpendicular to the front surface, and the resistance of the sheet in a direction parallel to the front surface being less than half of the first resistance. The apparatus according to any one of the preceding aspects.

[0067] Aspect 6: The apparatus according to any one of the preceding aspects, wherein the first layer of the anisotropic material includes graphite.

[0068] Aspect 7: The apparatus according to any one of the preceding aspects, wherein the first layer of the anisotropic material includes synthetic graphite.

[0069] Aspect 8: The apparatus according to any one of the preceding aspects, wherein the first layer of the anisotropic material comprises a sheet of pyrolytic graphite or a graphitized polymer film.

[0070] Aspect 9: The apparatus according to any one of the preceding aspects, wherein the first layer of the anisotropic material comprises graphite foil.

[0071] Aspect 10: The apparatus according to Aspect 9, wherein the first layer of the anisotropic material comprises graphite foil made from compressed high-purity exfoliated mineral graphite.

[0072] Aspect 11: The apparatus according to any one of the preceding aspects, wherein the layer of the dielectric material has an outer-facing surface opposite the skin-facing surface, the first layer of the anisotropic material has an outer-facing surface opposite the skin-facing surface, and the outer-facing surface of the layer of the dielectric material is in electrical contact with the skin-facing surface of the first layer of the anisotropic material.

[0073] Aspect 16: The apparatus according to Aspect 11, wherein the outer-facing surface of the first layer of the anisotropic material is in contact with the outer adhesive layer.

[0074] Aspect 13: The apparatus according to Aspect 11 or Aspect 12, wherein the skin-facing surface of the layer of the dielectric material is in contact with the skin contact layer.

[0075] Aspect 14: The apparatus according to any one of Aspects 1 to 10, wherein the layer of the dielectric material has an outer-facing surface opposite the skin-facing surface, the first layer of the anisotropic material has an outer-facing surface opposite the skin-facing surface, and the skin-facing surface of the layer of the dielectric material is in contact with the outer-facing surface of the first layer of the anisotropic material.

[0076] Aspect 15: The apparatus according to Aspect 14, wherein the outer-facing surface of the layer of the dielectric material is in contact with the outer adhesive layer.

[0077] Aspect 16: The apparatus according to Aspect 14 or Aspect 15, wherein the skin-facing surface of the first layer of the anisotropic material is in contact with the skin contact layer.

[0078] Aspect 17: The layer of at least one anisotropic material further includes a second layer of anisotropic material, and the layer of dielectric material is disposed between the first and second layers of anisotropic material, the device according to any one of Aspects 1 to 10.

[0079] Aspect 18: The layer of dielectric material has an outer surface opposite to the skin-facing surface, the first layer of anisotropic material has an outer surface opposite to the skin-facing surface, the second layer of anisotropic material has an outer surface opposite to the skin-facing surface, and the outer surface of the first layer of anisotropic material contacts the outer adhesive layer, the device according to Aspect 17.

[0080] Aspect 19: The skin-facing surface of the layer of dielectric material contacts the outer surface of the second layer of anisotropic material, the device according to Aspect 18.

[0081] Aspect 16: The skin-facing surface of the second layer of anisotropic material contacts the skin contact layer, the device according to Aspect 14 or Aspect 15.

[0082] Aspect 21: The layer of dielectric material is disposed between the first and second layers of anisotropic material, the device according to any one of Aspects 17 to 20.

[0083] Aspect 22: The layer of dielectric material includes a dielectric polymer, the device according to any one of the preceding aspects. The dielectric constant of the dielectric polymer can be 10 or more, such as 10 to 50,000.

[0084] Aspect 23: The dielectric material is a ceramic material, the device according to any one of Aspects 1 to 21.

[0085] Aspect 24: The dielectric material is a metal oxide, the device according to any one of Aspects 1 to 21.

[0086] Aspect 25: The dielectric constant of the dielectric material is 10 to 50,000, the device according to any one of the preceding aspects.

[0087] Aspect 26: The device according to aspect 1, further comprising a wire electrically connected to the outer adhesive layer.

[0088] Aspect 27: The device according to aspect 26, wherein the device does not include a circuit board or a flexible circuit.

[0089] Aspect 28: A device comprising: at least one layer of an anisotropic material; a layer of a dielectric material, wherein the layer of the dielectric material contacts at least a first layer of the at least one layer of the anisotropic material to form a capacitive structure; opposing layers of a conductive material, wherein the at least one layer of the anisotropic material and the layer of the dielectric material are disposed between the opposing layers of the conductive material.

[0090] Aspect 29: The device according to aspect 28, wherein the conductive material of at least one layer of the opposing layers of the conductive material is a conductive adhesive.

[0091] Aspect 30: The device according to aspect 28, wherein the conductive material of at least one layer of the opposing layers of the conductive material is a conductive gel.

[0092] Aspect 31: The device according to any one of aspects 28 to 30, wherein the conductive material of at least one layer of the opposing layers of the conductive material is a conductive grease.

[0093] Aspect 32: The device according to aspect 28, wherein the conductive material of at least one layer of the opposing layers of the conductive material is a conductive gel or a conductive adhesive.

[0094] Aspect 33: The device according to any one of aspects 28 to 32, further comprising a cover configured to apply a capacitive structure to a patient's skin.

[0095] Aspect 34: A method comprising generating an electric field using the device according to any one of the preceding aspects.

[0096] Aspect 35: The method according to aspect 34, wherein the electric field is an alternating electric field having a frequency of 50 kHz to 1 MHz or 100 kHz to 500 kHz.

[0097] While the present invention has been disclosed with reference to specific embodiments, many modifications, changes, and alterations to the described embodiments are possible without departing from the scope and scope of the invention as defined in the appended claims. Accordingly, the present invention is not intended to be limited to the described embodiments, but is intended to have the full scope defined by the language of the claims and their equivalents.

Explanation of reference numerals

[0098] 10 Device 20 Outer adhesive layer 22, 52 Conductive gel or conductive adhesive 30 Layer of anisotropic material 40 Layer of dielectric material 50 Skin contact layer 60 Circuit board 70 Metal pad

Claims

1. An apparatus comprising: an outer adhesive layer containing a conductive gel or a conductive adhesive; at least one layer of an anisotropic material; a layer of a dielectric material; a skin contact layer containing a conductive gel or a conductive adhesive, wherein the at least one layer of anisotropic material and the layer of dielectric material are disposed between the outer adhesive layer and the skin contact layer, and the layer of dielectric material contacts at least a first layer of the at least one layer of anisotropic material to form a capacitive structure.

2. The apparatus according to claim 1, further comprising a circuit board or a flexible circuit, wherein the circuit board or the flexible circuit is electrically connected to the outer adhesive layer.

3. The circuit board or the flexible circuit is electrically connected to the outer adhesive layer via at least one metal pad that makes electrical contact with the circuit board or the flexible circuit, and the surface area of each of the layer of dielectric material and the first layer of anisotropic material is larger than the total surface area of the at least one metal pad. The apparatus according to claim 2.

4. The apparatus according to claim 1, wherein the first layer of anisotropic material contains graphite.

5. The apparatus according to claim 1, wherein the first layer of anisotropic material contains a sheet of pyrolytic graphite, a graphitized polymer film, or a graphitized polymer foil made from compressed high-purity exfoliated mineral graphite.

6. The layer of dielectric material has an outer surface opposite to the skin-facing surface, the first layer of anisotropic material has an outer surface opposite to the skin-facing surface, and the outer surface of the layer of dielectric material is in electrical contact with the skin-facing surface of the first layer of anisotropic material. The apparatus according to claim 1.

7. The apparatus according to claim 6, wherein the outer surface of the first layer of anisotropic material contacts the outer adhesive layer.

8. The apparatus according to claim 6, wherein the skin-facing surface of the layer of dielectric material contacts the skin contact layer.

9. The layer of dielectric material has an outer surface opposite to the skin-facing surface, the first layer of anisotropic material has an outer surface opposite to the skin-facing surface, and the skin-facing surface of the layer of dielectric material contacts the outer surface of the first layer of anisotropic material. The apparatus according to claim 1.

10. The apparatus according to claim 9, wherein the outer surface of the layer of dielectric material contacts the outer adhesive layer.

11. The device according to claim 9, wherein the skin-facing surface of the first layer of the anisotropic material contacts the skin contact layer.

12. The device according to claim 1, wherein the at least one layer of anisotropic material further comprises a second layer of anisotropic material, and the layer of dielectric material is disposed between the first and second layers of anisotropic material.

13. The device according to claim 1, wherein the layer of dielectric material comprises a dielectric polymer.

14. A device comprising: at least one layer of anisotropic material; and a layer of dielectric material, the layer of dielectric material contacting at least the first layer of the at least one layer of anisotropic material to form a capacitive structure; and opposing layers of conductive material, the at least one layer of anisotropic material and the layer of dielectric material being disposed between the opposing layers of conductive material.

15. The device according to claim 14, wherein the conductive material of at least one of the opposing layers of conductive material is a conductive gel, a conductive adhesive, or a conductive grease.

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