Pumping and filtering approaches of thermoinduced dielectric modification in 2d and 3D structures

Abstract

A substrate with an electrode arrangement mounted on it for manipulating a liquid conductive medium is described. The electrode arrangement comprises electrode elements and at least one conductive track connecting the electrode elements. The conductive track is arranged such that, when connected to an alternating current source, it forms a circuit. The electrode elements are arranged in the circuit such that two opposing electrode elements form an electrode-counter electrode pair, and the electrodes and counter electrodes are arranged alternately. The substrate is suitable for mixing, transporting, pumping, or filtering the liquid conductive medium, or for separating components within the liquid medium.

Description

[0001] The invention relates to a substrate having an electrode arrangement applied thereon for manipulating a liquid conductive medium, a device comprising the substrate, a method for manipulating a liquid conductive medium by means of the device and an alternating current source, and the use of the substrate.

[0002] Contamination on surfaces, in hoses, or even on conveyor belts can be removed using direct methods, such as a sponge and solvent or aqueous soap solutions. Difficulties can arise in hard-to-reach areas. Such cleaning is usually not possible during operation, for example, during the transport of liquids in hoses.

[0003] Cleaning liquids or bodies of water contaminated by micro- and macroplastic particles is also problematic, especially if this is to be done independently.

[0004] Pump systems are typically used to transport liquids. Pump systems are usually constructed with moving parts, such as paddle wheels or peristaltic systems, which become brittle over time and can fail. Especially in extreme conditions, such as high G-forces, mechanical systems fail due to the gyroscopic effect and the pressure on the bearings.

[0005] Mixing liquids usually requires the use of mechanical stirring systems with moving parts.

[0006] Overall, conventional methods for manipulating liquids in the areas of cleaning, sorting, filtering, transporting, or pumping have disadvantages resulting from mechanical cleaning and associated abrasion, the use of environmentally unfriendly coatings (perfluorochemicals) and cleaning agents, and the use of mechanical devices such as pumping systems and agitators.

[0007] These conventional methods are not very sustainable because they require chemical and / or mechanical aids and the service life of the mechanical aids is limited.

[0008] EP 1465 729 B1 discloses a device for moving a fluid, comprising a substrate and several electrodes arranged parallel to one another. Unfortunately, this solution cannot ensure direction-dependent mixing processes.

[0009] The object of the present invention is to provide a substrate and a device for manipulating liquid conductive media that overcomes the disadvantages described above. In particular, the provided substrates and devices should enable the manipulation of liquid conductive media without the use of chemical and / or mechanical aids.

[0010] It was found that this task can be solved by using high-frequency cleaning, mixing, sorting and pumping systems, which are based on a static structure and can thus be applied locally on two- or three-dimensional surfaces and switched by electrical control.

[0011] The invention therefore relates to a substrate having an electrode arrangement applied thereon for manipulating a liquid conductive medium, wherein the electrode arrangement comprises electrode elements and at least one conductor track connecting the electrode elements, which are arranged such that the at least one conductor track forms an electrical circuit when connected to an alternating current source, and the electrode elements are arranged in the electrical circuit such that two opposing electrode elements each form a pair of electrode and counterelectrode, and electrodes and counterelectrodes are arranged alternately. The electrode and the counterelectrode of a pair are arranged at an angle such that the electrode elements are not arranged parallel, preferably at an angle of 0° to 45°, particularly preferably at an angle of 0° to 25°.

[0012] The attached drawings show in Fig. 1a a partial schematic plan view of an exemplary electrode arrangement on a substrate according to the prior art Fig. 1b a partial schematic plan view of a further exemplary electrode arrangement on a substrate according to the prior art Fig. 1c a partial schematic plan view of a further exemplary electrode arrangement on a substrate according to the prior art Fig. 2 a partial schematic cross section of a substrate according to the prior art in a liquid conductive medium with an applied alternating current Fig. 3 a partial schematic cross section of a substrate according to the invention in a liquid conductive medium with an applied alternating current Fig. 4 a partial schematic plan view of a further exemplary electrode arrangement with an angled arrangement of the electrode elements on a substrate according to the invention Fig.5 a schematic representation of a device according to the invention in the form of a hose.

[0013] The invention is explained in detail below.

[0014] An electrode array is applied to the substrate according to the invention for manipulating a liquid conductive medium. The substrate on which the electrode array is applied is naturally made of a virtually non-conductive or insulating material.

[0015] In this application, the manipulation of the liquid conductive medium is understood to mean, in particular, processes selected from the mixing of the liquid medium, transporting or pumping of the liquid medium and / or the sorting, separation or filtering of components contained in the liquid medium.

[0016] The substrate on which the electrode arrangement is applied can be made of an organic or inorganic material, e.g., a plastic, an elastomer, glass, or a ceramic; a plastic or elastomer substrate is preferred. Examples of suitable plastics are plastics made of polyester, polyvinyl chloride, polyurethane, or polyolefin, which may be crosslinked or uncrosslinked. Examples of suitable elastomers are elastomers made of thermoplastic elastomer (TPE) or crosslinked isoprene. An example of a suitable ceramic is aluminum oxide.

[0017] The substrate can be a hard or rigid, flexible, or elastic substrate. The substrate can be a single layer or a multilayer composite, which may optionally include a textile carrier. If the substrate is a multilayer composite, the above information on the material refers to the upper layer on which the electrode arrangement is applied.

[0018] The substrate can be, for example, a film, a foil, a sheet, a mat, a 3D structure such as a hose, a hose distributor, or a hose coupling, a plate, or artificial leather, with the substrate preferably being made of plastic. The sheet can be, for example, the inner surface of a hose. The substrate is particularly preferably a plastic film.

[0019] The plastic film can be, for example, a polyester, polyvinyl chloride, polyurethane, or polyolefin film, whereby the plastic can be cross-linked or uncross-linked. The plastic films, especially those mentioned above, can contain thermally conductive fillers, such as silicon carbide or aluminum oxide, to enable the heat generated at the electrode elements to be dissipated.

[0020] The electrode arrangement applied to the substrate comprises electrode elements and at least one conductor track. The electrode elements are electrically connected to the at least one conductor track.

[0021] The electrode elements and the at least one conductor track are formed from a conductive material. Furthermore, the electrode elements and the at least one conductor track can be applied to the substrate using the same method or a different method. As a rule, it is preferred that the electrode elements and the at least one conductor track are made of the same material and are applied to the substrate using the same method. The electrode elements and the at least one conductor track can be applied to the substrate simultaneously or sequentially.

[0022] Electrode elements and the at least one conductor track made of the same material are preferred for etched systems. In printed electronics, the same or different materials can be used for the electrode elements and the at least one conductor track.

[0023] Examples of materials for electrode elements and the at least one conductor track are independently conductive metals or conductive polymers. Examples of conductive metals are copper, zinc, tin, platinum, nickel, palladium, gold, silver, iridium, tungsten, or mixtures thereof. Examples of conductive polymers are polymers that are themselves conductive or polymers that contain conductive particles, e.g., made of carbon nanotubes (CNTs), graphite, or metal-coated CNTs, and thus become conductive. Preferred materials are silver or conductive polymers that contain CNTs or metal-coated CNTs.

[0024] Other suitable materials include metal mixtures, in which another metal, such as gold, platinum, or palladium, is deposited on a base metal, such as copper or nickel, e.g., by electrolytic deposition. This allows for better chemical resistance.

[0025] In addition to conductive polymers and metals, semiconductors can also be used. However, these must be operated at a voltage at which they become electrical conductors. One example is doped silicon, which also offers good chemical compatibility.

[0026] The electrode elements and the at least one conductor track can be applied to the substrate independently of one another using suitable application methods. Examples of suitable application methods include etching, spraying, printing, ablation, plasma deposition, sputtering, scanning, or combinations thereof. The electrode elements and / or the at least one conductor track, in particular the electrode elements, are preferably applied to the substrate by printing. Suitable printing methods include, for example, flexographic printing, gravure printing, screen printing, offset printing, inkjet printing, or pad printing. Rotary printing methods, such as flexographic printing or gravure printing, are particularly well-suited for the production of such printed electrode arrangements or electrode elements, as they enable high throughput.

[0027] In a preferred embodiment, therefore, the applied electrode elements are printed electrode elements, in particular the applied electrode arrangement is a printed electrode arrangement.

[0028] Suitable starting materials for applying the electrode elements and / or the at least one conductor track by plasma deposition are metals, in particular copper, zinc, tin, platinum, palladium, nickel, gold, silver, iridium, tungsten, or combinations thereof, or salts of these metals. Ideally, inert metal compounds are used.

[0029] Suitable fluids for printing the electrode elements and / or the at least one conductor track include, for example, solvent-based, solvent-free, or aqueous pastes, solutions or dispersions of metallic particles, in particular nano- or microparticles, metal salt solutions reduced by redox systems, or conductive polymers or dendrimers. Furthermore, mixing processes and mixed solutions can also be used. Conductive pastes are particularly preferred as the fluid.

[0030] After printing the fluid onto the substrate, post-treatment of the applied fluid is usually required to produce the electrode array. This post-treatment primarily solidifies the material. This post-treatment can be performed, for example, by convection or heat treatment, near-infrared (NIR) irradiation, infrared (IR) irradiation, ultraviolet (UV) irradiation, or photonic sintering.

[0031] In a preferred embodiment, the printed electrode elements, in particular the printed electrode arrangement, are produced by pattern-printing an electrically conductive paste onto the substrate and subsequently treating the printed paste by UV irradiation.

[0032] The number of interacting electrode elements in the electrode arrangement can vary widely. The electrode arrangement can, for example, have at least 2, preferably at least 4, more preferably at least 10, and particularly preferably at least 20 electrode elements. However, it can also contain significantly more electrode elements, e.g., at least 50 or at least 100 electrode elements. An alternating arrangement is also understood here to mean an arrangement consisting of an electrode and a counter electrode. With interacting electrode elements, two electrode elements are positioned opposite each other in such a way that a defined field can be created.

[0033] The electrode elements have a length and a width horizontally relative to the substrate plane and a thickness vertically relative to the substrate plane. The length is greater than the width and thickness, generally significantly greater.

[0034] It goes without saying that the dimensions of the electrode array on the substrate can vary considerably depending on the application. With today's available deposition techniques, such electrode arrays can be fabricated in the micrometer range, covering an area of, for example, 25 µm² or more. Of course, significantly larger electrode arrays, measuring several square meters, can also be created.

[0035] The electrode elements and the at least one conductor track connecting the electrode elements in the electrode arrangement are arranged such that the at least one conductor track forms an electrical circuit when connected to an alternating current source and the electrode elements are arranged in the electrical circuit in such a way that two opposing electrode elements each form a pair of electrode and counter electrode and electrodes and counter electrodes are arranged alternately.

[0036] The electrode elements have a length and a width horizontally relative to the substrate plane and a thickness vertically relative to the substrate plane. The length is greater than the width and thickness, generally significantly greater. The electrode elements are typically arranged parallel to one another, particularly when a linear movement orthogonal to the electrodes is desired. Furthermore, the electrode elements are typically arranged periodically in the electrode arrangement.

[0037] The embodiment according to the invention is an angled arrangement of the electrode elements, with the electrode and counter electrode of each pair being arranged at an angle. Such an embodiment is shown schematically in Fig. 4 The angle between the electrode and counter electrode of each pair can be in the range of 0° to 45°, preferably 0° to 25°. The angled arrangement allows, for example, directional mixing processes to be adjusted depending on the angle. This creates a flow from the smaller to the larger distance.

[0038] An alternating current source can be applied to the at least one conductor track or to both ends of the at least one conductor track, forming an alternating current circuit to which the electrode elements are connected. The electrode elements are arranged within the circuit.

[0039] The arrangement is designed so that when an alternating current is applied, two electrode elements form a pair of electrode and counterelectrode. The electrode and counterelectrode are arranged alternately, i.e., an electrode element acting as an electrode is followed by an electrode element acting as a counterelectrode, which in turn is followed by an electrode element acting as an electrode, and so on.

[0040] The distance (d1) between the electrode and counterelectrode of a pair is the distance from the center of the width of the electrode to the center of the width of the counterelectrode. The distance (d2) between two adjacent pairs of electrode and counterelectrode is the distance between the electrode elements of the two pairs that are closest to each other, based on the center of the width. For an angled arrangement of the electrode arrangement described above, the distances (d1) and (d2) each refer to the shortest distance between the two electrode elements under consideration.

[0041] In In one embodiment according to the prior art, the electrode arrangement is such that the volume of the electrode and counter electrode is equal and the distance (d1) between the electrode and counter electrode of one pair and the distance (d2) between two adjacent pairs of electrode and counter electrode are equal. Such an electrode arrangement is referred to herein as electrode arrangement A. In such an embodiment, Fig. 1a shown.

[0042] In one embodiment, the electrode arrangement is such that the volume of the electrode and counter electrode differs and / or the distance (d1) between the electrode and counter electrode of a pair differs from the distance (d2) between two adjacent pairs of electrode and counter electrode. Such an electrode arrangement is referred to herein as electrode arrangement A2. Variants of this embodiment are described in Fig. 1b, Fig. 1c and Fig. 3 shown.

[0043] An equal volume of two electrode elements generally means that the length, width, and thickness of both electrode elements are the same. A different volume of two electrode elements generally means that the electrode elements differ in width and / or thickness, generally width or thickness. The length of the electrode elements is usually the same.

[0044] The physical principles underlying the system are discussed below in the description of the method according to the invention.

[0045] The finished substrates with the applied electrode arrangement, in particular the printed electrode arrangement, are ready for use immediately after application or printing, or they can be laminated onto a wide variety of surfaces.

[0046] The invention also relates to a device for manipulating a liquid conductive medium, wherein the device is suitable for storing and / or transporting the liquid conductive medium and wherein a substrate according to the invention is arranged in the device as described above. The substrate according to the invention is arranged such that the electrode arrangement located thereon comes into contact with the liquid conductive medium when the liquid conductive medium is poured into the device or when the liquid conductive medium is introduced or passed through the device.

[0047] Examples of suitable devices include a container, a basin, a pipe or a pipeline, a hose or a hose line, a hose distributor, or a hose coupling. The device according to the invention can have one or more supply lines and / or one or more outlet lines for the liquid conductive medium. Furthermore, this technology can also be used for improved heat transfer from solar thermal systems or modules. The substrates according to the invention are optionally applied to surface collectors to reduce possible heating.

[0048] The substrate according to the invention can be freely arranged in the device, e.g. by hanging the substrate in the device or by fixing the substrate to the device by means of holding elements.

[0049] However, it is preferred that the substrate be applied to an inner surface of the device or be integrated into an inner surface of the device. The substrate can be applied to the entire inner surface of the device or, preferably, to a portion of the inner surface. Accordingly, the substrate can be integrated into or form the entire inner surface or, preferably, can be integrated into or form a portion of the inner surface. It is understood that the substrate is positioned such that the side with the electrode arrangement faces the interior space into which the liquid conductive medium is poured or introduced.

[0050] In a preferred embodiment, the substrate according to the invention with the electrode arrangement applied thereto is applied to an inner surface of the device, e.g., by laminating the substrate to an inner surface of the device. It is preferred that the substrate be flexible. A plastic film onto which the electrode arrangement is applied, preferably printed, is particularly suitable for this purpose.

[0051] In this way, the substrates with the electrode arrangement can be easily applied over the entire surface or, preferably, locally on two- or three-dimensional surfaces. Overall, a static structure without moving mechanical parts is obtained. The electrode arrangement can be switched by electrical control. For this purpose, the substrate according to the invention or the electrode arrangement located thereon is connected to an associated AC power source.

[0052] The invention further relates to a method for manipulating a liquid conductive medium by means of an alternating current source and a device according to the invention as described above, wherein the method comprises bringing the liquid conductive medium into contact with the electrode arrangement applied to the substrate in the device and applying an alternating current to the electrode arrangement by means of the alternating current source for manipulating the liquid conductive medium.

[0053] A liquid conductive medium is an electrically conductive liquid medium. The liquid medium usually contains one or more electrolytes, such as dissolved salts, ionic polymers, acids, or bases, to provide electrical conductivity. The minerals dissolved in normal tap water or other bodies of water are perfectly sufficient for this purpose. Distilled water does not exhibit suitable electrical conductivity. Electrolytes would need to be added to achieve electrical conductivity.

[0054] The liquid conductive medium can be a homogeneous or heterogeneous phase. Examples include an aqueous solution or dispersion, a liquid with an organic and aqueous phase, liquid salt systems, or liquids containing particles.

[0055] An example of a liquid with an organic and aqueous phase is an oil-water mixture, where, for example, thorough mixing is desired. A liquid salt system is a molten salt, e.g., a molten salt of ammonium acetate, which melts at approximately 115 °C and exhibits flow properties. If the materials of the substrate according to the invention, such as the substrate material and the electrode material, are suitable, molten salts of metal salts, such as lithium acetate, lithium citrate, or lithium chloride, can also be used.

[0056] An example of an aqueous solution is a saline solution, such as that used in molten salt reactors, molten salt batteries, or fuel cells. Here, mixing of the molten salt may be desirable to accelerate surface reactions.

[0057] The liquid containing particles can, for example, be an aqueous solution or dispersion containing particles. The particles can be made of any solid material, e.g. one or more types of plastic and / or an inorganic material. The particles can contain particles of the same or different materials. The particles can be made of a conductive and / or non-conductive material. For example, there can be particles with and without soot filling. The particles can also comprise particles with the same or different particle sizes, i.e. with a particle size distribution. The particles can, for example, be contaminants in the liquid, such as microplastics and / or macroplastics, which are to be removed from the liquid or separated according to certain criteria. Microplastics are generally understood to mean plastic particles with a diameter of less than 5 mm.

[0058] Depending on the application, the liquid conductive medium may also contain any other components, e.g. reactants that are to be mixed to accelerate the reaction or other components for which homogeneous mixing is desired.

[0059] The method according to the invention comprises bringing the liquid conductive medium into contact with the electrode arrangement applied to the substrate in the device. This can be done by pouring or introducing the liquid conductive medium into the device.

[0060] The method further comprises applying an alternating current to the electrode arrangement using the alternating current source to manipulate the liquid conductive medium. The alternating current can be applied periodically or continuously. When the alternating current source is switched on, a circuit is formed, and the alternating current flows through the electrode arrangement or the electrode elements, which, according to the arrangement, form electrodes and counterelectrodes, i.e., cathode and anode depending on the phase of the alternating current, and vice versa. When an alternating current is applied and the liquid conductive medium is in contact, alternating electric fields form at the electrodes and counterelectrodes, which can be symmetrical or asymmetrical depending on the electrode arrangement.

[0061] The dielectric constant is a material constant that depends, among other things, on temperature and applied frequency. Dielectric constants for specific materials are often given for 18 °C and 50 Hz, for example. The following discusses the processes that occur when an alternating current is applied to the electrode arrangement.

[0062] For example, the conductivity of a medium increases with increasing temperature, but the dielectricity decreases. This force causes the fluid to move.

[0063] The physical basis of the system can be explained as follows: If an alternating field is applied between the electrode elements of the electrode arrangement by applying the alternating current source, an electric field is formed between the electrode elements or between electrodes and counter electrodes.

[0064] The appropriate frequency of the alternating field and the appropriate applied voltage can vary depending on the application and can be adjusted using the alternating current source in the circuit. The applied alternating field can be set in ranges from low kHz to high MHz, e.g. in the range from 0.1 kHz to 20 MHz. Furthermore, voltages in the range from low mV (e.g. 1 mV or 5 mV) up to 100 V can be used. The alternating voltage must be selected so that electrolysis of the medium does not occur. The current strength is determined by the number of electrodes as well as the spacing and conductivity of the medium. If the current is too high, caused by the distances between the electrodes being too small at high conductivity, the voltage must be reduced accordingly or a current limiter must be installed. Alternatively, the electrode area can be reduced.

[0065] The basis for the system's function is the electrically conductive liquid medium, which experiences a change in dielectricity due to temperature changes. The smaller the distances between the electrode elements, the stronger the induced movement of the current-carrying medium.

[0066] The current flow in the circuit within the electrode array, generated by applying the alternating current source, causes a temperature change in the liquid conductive medium depending on the distance from the electrodes. A higher temperature can be set near the electrodes, while a lower temperature can be set further away. With the temperature change, the dielectricity of the material contained in the medium changes, decreasing with higher temperatures. This moment causes a macroscopic movement of the medium toward the electrodes.

[0067] The result is a mixing of the liquid conductive medium. Such an effect occurs, for example, in the symmetrical electrode arrangement A described above, as it is also shown in the Fig. 1a and 2 is shown.

[0068] The mixing of the liquid conductive medium can also be advantageous in that it achieves a cleaning effect and / or provides protection against contamination for the device surfaces maintained by the substrate. The macroscopic movement of the medium creates turbulence, which can loosen deposits on the surface and / or prevent the formation of deposits.

[0069] An electrode arrangement A as described above causes mixing of the medium, whereby the application of the alternating current leads to a macroscopic movement of the medium.

[0070] Additional effects can be achieved through asymmetrical electrode arrangements. The field strength of the resulting alternating electric fields in the liquid conductive medium depends on the thickness, length, and width, or the volume, of the electrode elements, as well as the spacing and arrangement of the electrode elements in the electrode arrangement. This can be used to shift the field lines in a specific direction, generating a one-sidedly amplified flow. This can, for example, lead to a unidirectional thrust, rather than homogeneous mixing between the electrodes, and thus to fluid pumping.

[0071] The consequence is that the liquid conductive medium is transported or pumped in one direction. Such an effect occurs, for example, in the asymmetrical electrode arrangement A2 described above. Such cases are also found in the Fig. 1b, 1c and 3shown.

[0072] An electrode arrangement A2 as described above causes the application of the alternating current to result in a directed movement of the medium.

[0073] If the medium contains particles made of conductive and / or non-conductive materials, such as those described above, these particles exhibit specific dielectric constants, which in turn influence the electric field lines. This makes it possible to purify particles based on their dielectric constant.

[0074] For example, if particles of the same size but made of different materials with high and low dielectric constants are present in the liquid conductive medium, this can result in the particles with a low dielectric constant being moved in one direction by the applied alternating field, e.g., being pumped to one side of the device, while other particles with a high dielectric constant are moved in a different direction by the applied alternating field, e.g., being pumped to the other side of the device. This achieves sorting, and appropriately arranged discharge lines in the device enable the different particles to be separated from one another.

[0075] In a similar way, particles of an identical material contained in a medium can also be sorted according to their size or their particle size distribution within the medium. The different particle sizes result in a different volume of the modified dielectric. This causes the particles to move in the field at different speeds depending on the particle size, thus also achieving sorting.

[0076] This makes it possible, for example, to sort different particles in the medium, such as different microplastics, according to their chemical composition and / or size. By suitably arranging drains, which can be closed if necessary, in the device, separation can also take place, which ultimately corresponds to filtration. A suitable device for this purpose could be a hose through which the liquid medium flows. The hose then has an area where the substrate according to the invention is arranged on the inner surface and, when an alternating voltage is applied, leads to a sorting of the particles contained in the liquid medium. Following this hose area, the hose can be provided with two drains which enable a separation of the sorted particles.

[0077] An expedient embodiment of the method according to the invention therefore comprises an electrode arrangement on the substrate, which is an asymmetrical electrode arrangement A2 as described above, and the liquid conductive medium contains particles, in particular plastic particles, such as microplastics, wherein the particles comprise particles of different sizes and / or different specific dielectric constants, so that the application of the alternating current leads to a directed movement of the particles, which differs in speed and / or direction depending on the size and the dielectric constant of the particles, thereby enabling a separation or sorting or filtration of the particles with regard to size and / or type.

[0078] As described above, the method according to the invention allows a liquid conductive medium to be used without moving mechanical parts for mixing, pumping, or transporting the medium with a homogeneous or heterogeneous phase. Furthermore, the possibility of sorting, separating, or filtering components such as particles in the liquid conductive medium has been described, e.g., small and large particles, e.g., microplastics, and sorting conductive plastic particles in a medium, such as particles with and without carbon black filling.

[0079] Further concrete examples of useful applications of the method according to the invention are given below.

[0080] The process according to the invention is suitable, for example, for mixing molten salt systems. Molten salt systems are used in molten salt reactors, molten salt batteries, or fuel cells. In particular, in the field of fuel cells, mixing using the process according to the invention can enable increased reactivity in the fuel cell, because the mixing can accelerate surface reactions.

[0081] A further field of application is liquid hoses in which liquid conductive media are passed through, in which the substrates according to the invention, e.g. in the form of a plastic film, with applied electrode arrangement are laminated onto the inner surface of the liquid hose or are integrated into the inner surface.

[0082] An applied alternating current then causes the medium in the hose to mix or swirl, which can lead to a reduction in friction and / or a cleaning effect. The possibility of reducing friction between the fluid and the surface can save energy, while also reducing effects such as biomolecule deposits on the inner surface of the hose.

[0083] Another example of the application of the method according to the invention for cleaning surfaces would be the cleaning of the surfaces of a swimming pool. The floors, walls and / or filters of the swimming pool can be partially or fully covered with the substrate according to the invention with an applied electrode arrangement. If a plastic film is used as the substrate, it can, for example, simply be glued to the corresponding surfaces. Of course, several substrates can also be used to line the surfaces. When the alternating current is applied, the water contained in the swimming pool is mixed, which can prevent the formation of deposits on the surfaces and / or lead to the removal of such deposits that are already present.

[0084] Alternatively, the method according to the invention can also be used as a detector for local conductivity concentrations, as well as for heating the medium, if appropriate currents are applied. By alternating alternating current and direct current, the conductivity of the medium or its resistance can be measured in direct current operation, provided the voltage and current values, or voltage and power values, are available.

[0085] This allows the medium near the surface to be selectively heated and, if necessary, a surface in the corresponding medium to be thermally disinfected. Especially with short electrode spacing in highly conductive media, high currents can lead to high local temperatures even in an alternating current field. This can be specifically used for the miscibility of, for example, oil-water emulsions. Here, improved dispersion can occur due to the local temperature increase caused by the decreasing surface energy of water with increasing temperature.

[0086] A further advantage of the high-frequency alternating field is that no electrode material is electrolytically degraded, built up or deposited.

[0087] Applications of all sizes are conceivable. This technology can be used to modify surfaces down to the microscale, i.e., to coat them with one or more substrates according to the invention. Large-scale applications of several square meters are also possible.

[0088] The invention further relates to the use of a substrate according to the invention as described above or of a device according to the invention as described above for manipulating a liquid conductive medium, in particular for mixing, transporting, pumping or filtering the liquid conductive medium or for separating or sorting components in the liquid conductive medium.

[0089] The invention further relates to the use of a substrate according to the invention as described above or of a device according to the invention as described above for cleaning surfaces or preventing the formation of deposits or for reducing the frictional resistance on inner surfaces, in particular in fluid hoses.

[0090] The use is advantageously carried out by a method according to the invention described above. Examples of such applications have also been described above. Further application examples follow.

[0091] Applications include, among other things, surface structures in both the 2D and 3D realms. These 3D structures can also be the interior surfaces of hoses, for example. The application allows multiple functions to be integrated into this hose. For example, immiscible media such as water and oil can be dispersed during the flow, and the resulting emulsion droplets can be defined by the excitation of the alternating current.

[0092] Additional functions include a reduction of flow resistance by triggering the reduction of surface effects.

[0093] By arranging the electrodes for pumping effects, hoses or plates can be used directly as pump units. This has the advantage of reducing weight and the number of units used. Mechanical moving parts are no longer required.

[0094] This is particularly suitable for high-speed applications where the liquid conductive medium is subjected to high G-forces, such as in aircraft applications. The liquid conductive medium can thus be manipulated without disturbing effects, such as the Coriolis force, on rotating mechanical parts.

[0095] Additional applications in hoses can include the separation of different particles, where the particles may differ in size and / or type. This allows, for example, particles contained in a liquid conductive medium contained in the hose, such as suspended particles, microplastics, or similar disruptive particles, to be separated. This would allow, among other things, longer service life for components, reduced wear, and more sustainable media purification.

[0096] Additional applications for the substrate or device according to the invention are in the cooling of batteries and accumulators, in particular in the high-performance sector, such as mobile applications, for highly efficient heat dissipation through reduced surface effects.

[0097] Another application is the mixing of liquid conductive media in which chemical reactions are to be carried out. In this way, chemical reactions can be significantly accelerated through near-surface triggered diffusion compared to large-scale reactors with conventional mixing systems. For example, biological conversion reactions have been accelerated by 5 to 50 times.

[0098] Electrode arrangements according to the prior art as well as the invention are explained below with reference to exemplary embodiments and drawings, which are not intended to limit the scope of the invention in any way.

[0099] Fig. 1a shows a partial schematic top view of an exemplary electrode arrangement on a substrate (not shown) according to the prior art. The section shows only a left-hand section of the arrangement. On the right-hand side (not shown), the upper and lower parts of the at least one conductor track 2 are connected to one another in order to close the circuit. Furthermore, the alternating arrangement of electrodes 3 and counterelectrodes 4 is continued there. The electrode arrangement shown is connected to the alternating current source 1 via the at least one conductor track 2. The electrode arrangement has a plurality of electrode elements, two of which each form a pair of electrode 3 and counterelectrode 4. The electrodes 3 and counterelectrodes 4 are arranged alternately.

[0100] In Fig. 1a A symmetrical electrode arrangement according to the electrode arrangement A described above is shown. In this electrode arrangement, the volume of the electrodes 3 and counterelectrodes 4 is equal. All electrode elements are identical in length, width, and thickness. Furthermore, the distance (d1) between electrode 3 and counterelectrode 4 of a pair and the distance (d2) between two adjacent pairs of electrode 3 and counterelectrode 4 are identical.

[0101] Fig. 1b shows a partial schematic plan view of another exemplary electrode arrangement on a substrate (not shown) according to the prior art. The arrangement corresponds, apart from the differences mentioned below, to that shown in Fig. 1a , so reference is made to it in this regard.

[0102] In Fig. 1b a variant of the asymmetrical electrode arrangement according to the electrode arrangement A2 described above is shown, which is referred to here as electrode arrangement B. In this electrode arrangement, the volume of the electrodes 3 differs from the volume of the counter electrodes 4. The different volume results from the fact that the width (w1) of the counter electrodes differs from the width (w2) of the electrodes. The length and thickness of all electrode elements are the same. Furthermore, the distance (d1) between the electrode and counter electrode of a pair and the distance (d2) between two adjacent pairs of electrode and counter electrode are the same. Due to the asymmetrical electrode arrangement, the field lines formed in the method according to the invention are shifted in a specific direction, whereby a one-sidedly amplified flux is generated.

[0103] Fig. 1c shows a partial schematic plan view of another exemplary electrode arrangement on a substrate (not shown) according to the prior art. The arrangement corresponds, apart from the differences mentioned below, to that shown in Fig. 1a , so reference is made to it in this regard.

[0104] In Fig. 1c A variant of the asymmetrical electrode arrangement according to the electrode arrangement A2 described above is shown, which is referred to here as electrode arrangement C. In this electrode arrangement, the volume of the electrodes 3 and counterelectrodes 4 is equal. All electrode elements are identical in terms of length, width, and thickness. However, the distance (d1) between the electrode and counterelectrode of a pair differs from the distance (d2) between two adjacent pairs of electrode and counterelectrode. Due to the asymmetrical electrode arrangement, the field lines formed in the method according to the invention are shifted in a specific direction, thereby generating a one-sidedly amplified flux.

[0105] Fig. 2 shows a partial schematic cross-section of a substrate 5 in a liquid conductive medium 6 with an applied alternating current. On the substrate 5 is the electrode arrangement, of which a pair of electrode 3 and counter electrode 4 is shown in cross-section. Fig. 2 The electrode arrangement shown is the one in Fig. 1a shown symmetrical electrode arrangement A.

[0106] The liquid conductive medium 6 is in contact with the electrode array. The applied alternating voltage causes an alternating current to flow through the array, generating a symmetrical alternating electric field 7 between electrode 3 and counter electrode 4. The alternating field creates a temperature gradient T in the medium 6, as the temperature increases more sharply near the electrodes than in more distant areas of the medium. Since the dielectricity of the medium material decreases at higher temperatures, a corresponding dielectric gradient D is generated. This moment causes a macroscopic movement of the medium toward the electrodes. As a result, mixing of the liquid conductive medium occurs.

[0107] Fig. 3 shows a partial schematic cross-section of a substrate 5 in a liquid conductive medium 6 with an applied alternating current. On the substrate 5 is the electrode arrangement, of which a pair of electrode 3 and counter electrode 4 is shown in cross-section. Fig. 3 The electrode arrangement shown is a variant of an asymmetrical electrode arrangement according to the described electrode arrangement A2. In this variant, the different volumes of electrode 3 and counter electrode 4 result from the different thicknesses of electrode 3 and counter electrode 4.

[0108] The liquid conductive medium 6 is in contact with the electrode arrangement. The applied alternating voltage causes an alternating current to flow through the arrangement, generating an alternating electric field 7 with shifted field lines between electrode 3 and counter electrode 4. The alternating field creates a temperature gradient T in the medium 6, as the temperature increases more sharply near the electrodes than in areas of the medium further away. Since the dielectricity of the medium material decreases at higher temperatures, a corresponding dielectric gradient D is generated. The shifted alternating field 7 generates a one-sidedly amplified flow. This leads to a unidirectional push, indicated by the dashed arrows, rather than a homogeneous mixture between the electrodes.

[0109] Fig. 4 shows a partial schematic top view of another exemplary electrode arrangement on a substrate according to the invention, wherein the electrode elements have an angled arrangement, with electrode 3 and counterelectrode 4 of a respective pair having an angled arrangement. The angle can be approximately 15°, for example. Due to the angled arrangement, directional mixing processes can be adjusted depending on the angle.

[0110] Fig. 5 shows a schematic representation of a device according to the invention in the form of a tube. The tube 8 can be a conventional tube, e.g. a plastic tube, on the inside of which a substrate 5 according to the invention with an applied electrode arrangement 9 is located. The electrode arrangement 9 can, for example, be an arrangement as shown in the Fig. 1a, 1b, 1c , 2, 34 and 5, respectively. The electrode arrangement can be connected to an alternating current source via provided power connections 10, particularly for high-frequency current. The substrate can, for example, form the inner layer of the tube, ie, be integrated therein, or be a plastic film applied to the inside of the tube with the applied electrode arrangement 9.

[0111] By applying an alternating current to the electrode arrangement 9, a liquid conductive medium contained in the tube can be manipulated. The manipulation can involve, for example, mixing or pumping the medium or sorting different components within the medium. List of reference symbols

[0112] 1 Alternating current source 2 Conductor track 3 Electrode element (electrode) 4 Electrode element (counter electrode) 5 Substrate 6 Liquid conductive medium 7 Alternating electric field 8 Hose 9 Electrode arrangement 10 Current connections d1 Distance between electrode and counter electrode of a pair d2 Distance between two adjacent pairs of electrode and counter electrode w1 Width of electrode element (counter electrode) w2 Width of electrode element (electrode) TTemperature gradient D Dielectric gradient for material of the medium

Claims

1. Substrate (5) with an electrode arrangement (9) applied thereon for manipulating a liquid conductive medium (6), wherein the electrode arrangement (9) comprises electrode elements (3, 4) and at least one conductor track (2) connecting the electrode elements (3, 4), which are arranged such that the at least one conductor track (2) forms an electric circuit when connected to an alternating current source (1) and the electrode elements (3, 4) are arranged in the electric circuit in such a manner that in each case two mutually opposing electrode elements (3, 4) form a pair composed of electrode (3) and counterelectrode (4) and electrodes (3) and counterelectrodes (4) are arranged alternately, characterized in that the electrode (3) and the counterelectrode (4) of a pair are arranged at an angle so that the electrode elements (3, 4) are not arranged parallel, preferably at an angle of 0° to 45°, particularly preferably at an angle of 0° to 25°.

2. Substrate (5) according to Claim 1, wherein the substrate (5) is a sheet, a film, a web, a mat, a plate or an artificial leather, wherein the substrate (5) is preferably composed of plastics material, wherein the substrate (5) is in particular a plastics film.

3. Substrate (5) according to Claim 1 or 2, wherein the applied electrode elements (3, 4) are printed electrode elements (3, 4), wherein the applied electrode arrangement (9) is preferably a printed electrode arrangement (9).

4. Substrate (5) according to Claim 3, wherein the printed electrode elements (3, 4), preferably the printed electrode arrangement (9), are / is obtainable by patternwise printing of an electrically conductive paste onto the substrate (5) and subsequent treatment of the paste by UV irradiation.

5. Substrate (5) according to any of Claims 1 to 4, wherein the electrode arrangement (9) is an electrode arrangement A or an electrode arrangement A2, - wherein in the electrode arrangement A, the volume of electrode (3) and counterelectrode (4) is the same and the distance (d1) between electrode (3) and counterelectrode (4) of a pair and the distance (d2) between two adjacent pairs of electrode (3) and counterelectrode (4) are the same, - wherein in the electrode arrangement A2, electrode (3) and counterelectrode (4) have different volumes and / or the distance (d1) between electrode (3) and counterelectrode (4) of a pair is different from the distance (d2) between two adjacent pairs of electrode (3) and counterelectrode (4).

6. Substrate (5) according to any of Claims 1 to 5, wherein the manipulation of the liquid conductive medium is selected from - mixing of the liquid medium - transporting or pumping of the liquid medium - sorting, separating or filtering of constituents contained in the liquid medium.

7. Device for manipulating a liquid conductive medium, wherein the device is suitable for storing and / or transporting a liquid conductive medium and a substrate (5) according to any of Claims 1 to 6 is arranged in the device.

8. Device according to Claim 7, wherein the device is a container, a basin, a tube or a hose (8), wherein the device can have one or more supply lines and / or one or more discharge lines for the liquid conductive medium.

9. Device according to Claim 7 or 8, wherein the substrate (5) is applied on an inner surface of the device or is integrated in an inner surface of the device.

10. Method for manipulating a liquid conductive medium by means of an alternating current source (1) and a device according to any of Claims 7 to 9, wherein the method comprises contacting the liquid conductive medium with the electrode arrangement (9) applied on the substrate (5) in the device and applying an alternating current to the electrode arrangement (9) by means of the alternating current source (1) for the manipulation of the liquid conductive medium.

11. Method according to Claim 10, wherein the electrode arrangement (9) on the substrate (5) is an electrode arrangement A according to Claim 5, wherein applying the alternating current results in a macroscopic movement of the medium, which causes mixing of the medium.

12. Method according to Claim 10, wherein the electrode arrangement (9) on the substrate (5) is an electrode arrangement A2 according to Claim 5, so that applying the alternating current results in a directional movement of the medium, which causes transporting or pumping of the medium.

13. Method according to Claim 10 or 12, wherein the electrode arrangement (9) on the substrate (5) is an electrode arrangement B according to Claim 5 and the liquid conductive medium contains particles, in particular plastics particles, such as microplastics, wherein the particles comprise particles of different sizes and / or with different dielectric constants, wherein applying the alternating current results in a directional movement of the particles which differs in speed and / or direction depending on the size and dielectric constant of the particles, whereby separating or sorting or filtering of the particles with respect to size and / or type is made possible.

14. Method according to any of Claims 10 to 13, wherein the liquid conductive medium is a homogeneous or heterogeneous phase, e.g. an aqueous solution or dispersion, a liquid with organic and aqueous phases, a liquid containing particles, or a liquid salt system.

15. Use of a substrate (5) according to any of Claims 1 to 6 or a device according to any of Claims 7 to 9 for manipulating a liquid conductive medium, in particular for mixing, transporting, pumping or filtering the liquid conductive medium or for separating or sorting constituents, in particular particles, in the liquid conductive medium.

16. Use according to Claim 15, wherein the substrate (5) is arranged on an inside of a hose (8), in particular for mixing, dispersing and / or pumping a liquid conductive medium situated in the hose (8) and / or for separating or segregating constituents such as different particles that are present in the liquid conductive medium situated in the hose (8).

17. Use of a substrate (5) according to any of Claims 1 to 6 or a device according to any of Claims 7 to 9 for cleaning surfaces or for preventing formation of deposits on surfaces or for reducing the frictional resistance on internal surfaces, in particular in the case of liquid hoses.

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