Additive production method with modification to partial layers

Abstract

The invention relates to an additive production method, comprising the following steps: additively applying a material layer (1); and modifying a part of the applied material layer (1) in terms of properties, so that a partial layer (3) is structured in the material layer (1), the partial layer (3) being different from the remaining material layer at least in terms of the modified properties. The invention further relates to a correspondingly produced component and to a suitable production plant.

Description

Technical Field

[0001] The present application relates to an additive production method, during which partial layers in a structural element are modified. Background Art

[0002] Numerous additive manufacturing methods are known in the prior art. Additive manufacturing allows structural elements to be structured even in unusual shapes without material losses due to subsequent processing. The shaping of the structural element takes place during its production.

[0003] Nevertheless, in the prior art, the additive production of components is limited or difficult or even impossible for certain components. For example, electronic or catalytically active components are usually arranged separately in or on the components and cannot be printed in an additive production process.

[0004] An exemplary method for applying an electrically conductive component to a particularly 2D substrate and modifying it is to apply a substrate material and subsequently modify it by means of a laser-induced graphene process, which is known, for example, from the publications US 2020 / 0 112 026 A1, US 2020 / 0 348 121 A1, CN 111 879 341 A or WO 2018 085789 A1.

[0005] It is also possible to increase the conductivity of the modified LIG material in a post-processing step as described in the publications CN 109 440 145A, US 2018 / 0 199 441 A1 and WO 2020 197 606 A2.

[0006] Furthermore, the publications US 2021 / 0 395 420 A1 and WO 2017 051 182 A1 disclose high-temperature-resistant materials from the prior art.

[0007] CN 114322741 A describes by way of example a method for producing a ceramic membrane sensor. For this purpose, a metal component is provided as a substrate and a precursor layer for a ceramic insulating membrane is applied, for example, by screen printing. However, the method does not allow for structuring of partial layers in the already printed text.

[0008] DE 10 2019 101 268 A1 discloses a method for producing and modifying an object containing silicon carbide.

[0009] WO 2017 / 176251 A1 describes a printing method in which a photosensitive additive is distributed onto sections of a previously applied polymer layer using a liquid ink as a medium.

[0010] US 2018 / 0129002 A1 discloses various possible post-processing steps for surface treatment of electrical components produced in an additive manner.

[0011] US 9,827,713 B1 and WO 2020 / 236455 A1 finally disclose a special device for 3D printing, which has a plurality of processing stations in which the individual steps of the printing method are carried out.

[0012] No. 9,827,713 B1 describes a robot arm which immerses a substrate in different resins at a plurality of workstations in order to form different layers of a component.

[0013] In WO 2020 / 236455 A1, a plurality of plates are melted one after the other to form layers of a component. Summary of the invention

[0014] The object of the present application is to provide a method, a structural element and a device which overcome the disadvantages of the prior art.

[0015] The invention relates to an additive production method comprising a plurality of steps.

[0016] In a first step, a material layer is applied in an additive manner. The layer can be applied, for example, to a structural plate provided for this purpose or to a layer previously applied in an additive manner. The layer can include any material suitable for additive production or 3D printing.

[0017] In a further step, at least a portion of the previously applied material layer is modified in terms of properties, so that a partial layer in the material layer is structured. A partial area of ​​the material layer can be referred to here as a partial layer. The partial layer differs from the remaining material layer at least in terms of the material properties outside the modified portion of the layer. In one embodiment, the entire material layer is modified.

[0018] During the modification, in particular the chemical, physical, morphological and / or structural properties of the material layer can be changed. In particular, in different embodiments of the invention, the conductivity, porosity or particle size of the material layer can be changed, or an organic material can be carbonized into an inorganic carbon material.

[0019] For example, a portion of an applied material layer is modified in such a way that the electrical conductivity in this portion of the layer is changed and a partial layer is thereby structured whose electrical conductivity differs from the electrical conductivity of the remaining material layer.

[0020] During the modification, various properties of the material layer can be changed by the modification step. Then, after the modification, the structured partial layer can differ from the remaining material layer, for example, not only in its electrical conductivity but also in porosity and particle size.

[0021] The method described can produce layer structures with different desired properties without the need to print individual layers for this purpose. In addition, the properties of the printed material layers can already be adapted during the additive manufacturing process, thereby eliminating the need for corresponding post-processing steps.

[0022] Furthermore, targeted changes in the properties of previously additively produced layers enable the additive production of components with properties that cannot be produced in conventional additive production processes. These properties include in particular the previously mentioned properties, namely electrical conductivity, grain size, porosity and other similar material properties.

[0023] After the material layer has been applied and modified, another material layer can be applied in a further method step and modified again in such a way that at least one material property is changed in a portion of the layer and a partial layer is thus structured, which differs in terms of the material property in terms of electrical conductivity from the remaining material layers. Alternatively, a material layer can also be applied in which no partial layer is modified.

[0024] In particular, the partial layer can be structured in such a way that it is adapted to the partial layer in the first material layer and the two partial layers form, for example, a continuous layer with homogeneous properties.

[0025] In one embodiment, in particular, the same electrical conductivity is provided in each case in a partial layer and in another partial layer. An electrically conductive layer, for example an internal electrode, can then be structured in an electrically non-conductive material.

[0026] In one embodiment, a material layer and another material layer are applied directly one above the other or directly side by side. In other embodiments, the material layers can be applied not only side by side but also one above the other.

[0027] The material layer can consist of different materials, in particular of a structural material and a modifiable material.

[0028] In particular, different materials are applied in several steps of the printing process. The structural material is not suitable for the described modification steps, but predetermines the desired structure of the structural element to be produced.

[0029] The alterable material is suitable for alteration during the alteration step. Thus, a portion of the alterable material can be altered to produce a structure with desired properties.

[0030] The modifiable material should preferably be a temperature-resistant material which can be 3D printed in particular by means of bath-based photopolymerization, such as, for example, the plastic grades ThermoBlast or DL-400.

[0031] A material can also be considered "heat-resistant" here if it withstands an ambient temperature of at least 300° C. Correspondingly, the melting point or decomposition point of the heat-resistant material is above 300° C. and the structure of the heat-resistant material is not changed at temperatures up to 300° C.

[0032] This can be, for example, an active layer or an internal electrode in the material layer. The remaining, unmodified material layer continues to contribute to the overall structure of the component.

[0033] In one embodiment, the material layer or the further material layer comprises a ceramic material.

[0034] In another embodiment, the material layer or the further material layer comprises a metal.

[0035] In a part of the applied material layer, the layer material can then be modified by sintering and the partial layer can then be structured. The partial layer can include a metallic material or a ceramic material, for example, or consist of such a material.

[0036] Targeted, spatially resolved sintering allows for the structuring of specific partial layers with desired properties. For example, a ceramic material can be modified during sintering so that an electrically conductive metallic partial layer is formed in the ceramic layer. For example, an organic material with metallic or ceramic inserts can be modified so that the organic components are removed and a metallic or ceramic partial layer is formed, which in this case includes metal or ceramic or consists of such a material.

[0037] Furthermore, the porosity of the partial layers can be modified by sintering. In particular, structures with larger pores can be formed. By modifying the pores, for example, the suitability of the material as a catalyst, carrier material or filter element can be set.

[0038] In another embodiment, the material layer or another material layer comprises an organic material or consists of an organic material. In the organic material, in particular plastic, preferably ceramic and / or metal materials are additionally inserted, which can be modified as described above, for example.

[0039] Preferably, the material layer or the further material layer comprises plastic or consists of plastic.

[0040] Furthermore, natural materials such as, for example, cellulose-based materials, modified natural materials such as, for example, rubber, viscose and cellophane may also be used as organic materials.

[0041] Different plastics can be used. It is particularly preferred to use a homogeneous material layer consisting of a uniform base material. Possible materials are, for example, PI, PEI, PE, PP, etc.

[0042] In addition, mixtures of two pure plastic materials, i.e. non-chemically cross-linked mixtures or chemically cross-linked copolymers, such as ABS, are also conceivable. In other embodiments, the material of the material layer also includes composite materials such as GSK or PCB or polymer materials with fillers (such as, for example, with embedded ceramic particles or metal particles).

[0043] In one embodiment, partial layers can be structured in the plastic material by converting the plastic into inorganic carbon.

[0044] Particularly preferably, it is a heat-resistant plastic on which a laser-induced graphene process can be used and which can be 3D printed in particular by means of bath-based photopolymerization. In particular, heat-resistant plastics are suitable for using LIG processes due to their chemical composition and their processability at high temperatures. Here, organic materials can be converted in a targeted manner into graphene structures or graphite structures of carbon by means of a laser.

[0045] The plastic component preferably includes at least one monomolecular or oligomeric chemical species, each of which includes at least one carbon-carbon double bond that can be polymerized by free radical polymerization, wherein the monomolecular or oligomeric chemical species is present in a total amount of 25 to 99 weight percent relative to the plastic component.

[0046] Preferably, the plastic component also includes at least one photoinitiator, particularly preferably a cyclopentadienyl titanium photoinitiator, which is preferably present in a total amount of 0.1 to 15 weight percent, and the plastic component also includes at least one coinitiator, particularly preferably a thiol coinitiator, which is preferably present in a total amount of 0.5 to 20 weight percent.

[0047] Alternatively, the plastic component comprises, for example, a heat-curable component A having one or more chemical species selected from the group consisting of monomers and / or oligomers and / or prepolymers of maleimide derivatives according to formula (I) and isomers thereof, wherein:

[0048] n is an integer between 1 and 10,

[0049] R1 represents H, CH3 or CH2, and

[0050] R2 independently represents a linear, branched or cyclic, aliphatic or aromatic C5-C40 residue from one or more of the following groups, namely: phenyl, benzyl, phenethyl, methyl, ethyl, propyl, butyl, pentyl, hexyl, octyl, decyl, dodecanol, acetic acid, propionic acid, butyric acid, pentanoic acid, undecanoic acid, dodecanoic acid, benzoic acid and the corresponding esters, alkyl esters or aromatic esters, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, adamantyl, isobornyl, propenyl, biphenyl, naphthyl, anthracenyl, pyrenyl, bis(methylene)hydroxy, bis(ethylene)hydroxy, bis(phenyl)methane, bis(phenyl)ethane, bis(phenyl)propane, bis(phenyl)butane, bis(phenyl)ether, bis(phenyl)sulfide, bis(phenyl)amino or bis(phenyl)sulfone,

[0051]

[0052] Furthermore, the plastic composition then comprises a photohardenable component B having one or more chemical species selected from the group of (meth)acrylate, (meth)acrylamide, vinyl ester, vinyl, propenyl, alkynyl or styrene compounds or derivatives thereof, which is replaced with at least one molecule from the group in which the component A is selected, wherein the amount of the component A is in the range of 30 wt % to 95 wt % relative to the total weight of the components A and B, and the amount of the photohardenable component B is in the range of 5 to 70 wt % relative to the total weight of the components A and B.

[0053] Particularly preferably, component A then comprises a species of component A, wherein n is an integer from 2 to 10, which species has an aromatic residue which is preferably bonded to the N atom of the maleimide ring of formula I via a methylene group in an amount in the range of 20 to 100 weight percent, preferably 30 to 100 weight percent and further preferably 40 to 100 weight percent, relative to the total weight of component A.

[0054] The partial layers in the plastic can be modified by means of suitable methods and in particular can be converted into inorganic carbon. Examples of such suitable methods are thermal methods, mechanical methods such as grinding or roughening, or ultrasonic methods, the use of plasma, irradiation, for example by electron beams, lasers, UV-VIS radiation, IR radiation or X-ray radiation, microwave radiation, and chemical methods such as, for example, etching or chemical activation of the surface.

[0055] For example, partial layers in plastics can be structured by means of a laser-induced graphene process. In a laser-induced graphene process (also known as a LIG process), the material being processed is chemically and / or physically excited and changed by the action of laser radiation at the point of impact of energy. In particular, a thermal conversion or thermal decomposition is initiated at the point of impact.

[0056] In particular, in the LIG process, the organic carbon of the plastic is then converted into inorganic carbon variants, such as graphene, graphite or fullerenes ("carbonization") in a spatially resolved manner by targeted energy input by means of laser radiation. The LIG process is then generally not limited to the specific conversion of carbon into graphene, but can also include the conversion of carbon into other inorganic variants.

[0057] In particular, electrically conductive carbon structures can then be formed in the material layer. Furthermore, the inorganic carbon variants mentioned can also differ, for example, in their porosity and crystallinity.

[0058] In particular, the LIG process allows targeted modifications to be made on the surface of the material layer or modifications to be made which penetrate deeper into the material layer and in particular cover the entire thickness of a partial layer.

[0059] In one embodiment, the material layer comprises auxiliary materials which support the laser-induced graphene process, such as in particular catalysts, predopants or reactive groups.

[0060] For example, metal particles, metal salts or metal complexes dispersed in the layer can be used as catalysts.

[0061] In particular, the carbon material to be produced and its derivatives can be used as predopant.

[0062] In various embodiments, for example short-chain organic molecules having suitable reactive (terminal) groups, such as, for example, aromatic groups, are used as reactive groups.

[0063] The auxiliary materials mentioned are preferably used in trace amounts. The process is preferably carried out without significant addition of auxiliary materials. The auxiliary materials may in particular already be present in trace amounts in the raw materials used.

[0064] In one embodiment of the method, the structured partial layer is subjected to a post-treatment step in order to further modify the properties of the partial layer and in particular to enhance the properties set by the modification. Preferably, a surface treatment is performed on the structured partial layer at the surface of the material layer.

[0065] The desired properties of the finished component can then already be set during the additive production process.

[0066] In one embodiment in which the structured partial layer has at least an increased electrical conductivity compared to the remaining material layer, a possible post-treatment step comprises a surface treatment of the structured partial layer in order to further increase the electrical conductivity of the partial layer.

[0067] Surface treatment includes, for example, processes such as electroplating, spraying or screen printing or partial steps thereof. However, surface treatment is not limited to the processes mentioned. The processes mentioned can in particular apply a surface coating of a metal with high electrical conductivity. Thus, the electrical conductivity of a partial layer can be significantly increased.

[0068] Another alternative to surface treatment is to apply a catalyst in order to enhance the catalytic properties of the altered material. In this context, a catalyst is any form of a catalytically active material that can be applied, for example, in powder form. The catalyst can in particular be applied to the surface or introduced into the pores of the altered material.

[0069] In one embodiment, in an optional step, a seed layer is applied to the surface of the structured partial layer before one of the surface treatment steps mentioned, which seed layer serves as a basis for the subsequent surface treatment. In particular, such a seed layer can facilitate the application of the metallic material and thereby, for example, simplify and / or accelerate a plating process or a screen printing process or a spraying process. In particular, the seed layer can be a nanoscale seed layer.

[0070] In some embodiments, the structured partial layer has at least an increased porosity compared to the remaining material layer.

[0071] In an optional post-treatment step, an electrically conductive material can then be introduced into the pores of the structured partial layer and thus increase the electrical conductivity of the material.

[0072] In one embodiment, a post-processing step is preferably carried out before applying a further material layer. Thus, each individual material layer can be modified individually and specifically or the modified properties can be enhanced.

[0073] Additive production itself, ie the additive application of material layers (3D printing), can be carried out by means of any suitable production method, such as photopolymerization, material extrusion, material jetting, binder jetting, powder bed fusion, direct energy deposition or thin film lamination.

[0074] The method, photopolymerization curing, is particularly suitable for the process described here due to its high precision.

[0075] In one embodiment, multiple partial layers in the material layer are structured in one step. For this purpose, the material layer is irradiated with multiple lasers, for example, so that multiple LIG processes are carried out in parallel. Similarly, multiple sintering processes or similar modification steps can also be carried out in parallel at multiple sections of the material layer.

[0076] Preferably, in the method, the structural element is formed from a plurality of material layers, wherein in a plurality of the material layers a partial layer is then structured in each case as described.

[0077] Preferably, no structured partial layer is formed in at least one material layer. Such a material layer can be composed of a structural material in particular. The structural material can be an unchangeable material. Such a layer can, for example, increase the stability of the structural element or define the structure of the structural element.

[0078] The structured partial layers can be arranged arbitrarily or in a specific system. In one embodiment, the structured partial layers are arranged so that a plurality of partial layers of adjacent material layers adjoin each other. For example, a plurality of electrically conductive modified partial layers can adjoin each other so that an internal electrode is formed in the structural element.

[0079] In the embodiment of the production method, auxiliary steps can be carried out in any desired number and sequence between and / or after the aforementioned production steps. These are in particular steps of cleaning, washing, rinsing, neutralizing, activating, drying, etc. The precise selection and sequence depends, for example, on the component to be produced, its desired properties, the materials used or the additive production method used.

[0080] In particular, if the applied and modified material layer can be present as a green layer, a step for removing the binder and sintering follows.

[0081] Furthermore, in the embodiment of the production method, further, usually final steps follow, which are carried out after the application of the last material layer. This may involve, for example, shaping, external metallization, insulation, painting, binder removal and sintering. The specific steps preferably depend on the component to be produced, its desired properties, the materials used or the additive manufacturing method used. The steps can be carried out successively or simultaneously.

[0082] The invention also relates to an electrical component produced according to the described method. Such a component can have all the properties described above in the course of the described method.

[0083] In one embodiment, the structural element comprises a plurality of material layers, wherein a plurality of the material layers comprise structured partial layers having increased electrical conductivity. In a preferred embodiment, no structured partial layers are formed in at least one material layer.

[0084] In particular, the electrical component can be designed as a container, for example as a plate-shaped capacitor. The plate of the capacitor is then preferably oriented perpendicularly to the stacking direction of the additive production method. The internal electrodes of the capacitor are formed by a plurality of adjacent modified partial layers with increased electrical conductivity. Between them, there are unmodified sections with lower electrical conductivity or no electrical conductivity in each material layer.

[0085] The invention also relates to a device for carrying out the described process for producing a structural element. The device comprises at least one transport system and individual processing stations at which the steps of the process are carried out. The transport system is then designed such that the structural element can be transported from station to station in the operating state or the station can be moved to the structural element. As a result, all processing steps of the method can be carried out with the aid of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0086] The present invention is described in more detail below based on the embodiments and drawings. The present invention is not limited to the embodiments shown in the following drawings. Among them:

[0087] Figure 1 A working plate having additively applied layers of material is shown;

[0088] Figure 2 shows a material layer after modification for forming a partial layer;

[0089] Figure 3 Post-processing of the surface of the altered material layer is shown;

[0090] Figure 4 shows the structural element after application of a second material layer;

[0091] Figure 5 A structural element having two altered material layers is shown;

[0092] Figure 6 showing post-processing of the surface of the second altered material layer;

[0093] Figure 7 shows the structural element after application of a third material layer;

[0094] Figure 8 An alternative embodiment of the structural element after forming a partial layer in the first material layer is shown;

[0095] Fig. 9 An alternative embodiment of the structural element after forming a partial layer in the second material layer is shown;

[0096] Fig.10 An exemplary structural element is shown in cross-section with various layers of material arranged one above the other and side by side;

[0097] Fig.11 Another exemplary structural element is shown having different material layers;

[0098] Fig.12 Microscopic photographs of porous LIG-modified plastic materials are shown.

[0099] Similar or apparently identical elements in the drawings are provided with the same reference numerals. The drawings and the dimensional ratios in the drawings are not true to scale. DETAILED DESCRIPTION

[0100] Figures 1 to 7 An exemplary additive production process is schematically shown. Figure 1 In the first step shown, a material layer 1 is applied to a work plate 2. The material layer 1 is applied by means of a suitable additive method. Examples of suitable additive methods here are photopolymerization curing (VPP), material extrusion (MEX), material jetting (MJT), binder jetting (BJT), powder bed fusion (PBF), direct energy deposition (DED) and sheet lamination (SHL). The method VPP is preferred in particular due to its high printing accuracy. Other commonly used additive methods can also be used.

[0101] The material layer 1 comprises, for example, a single homogeneous material. When forming further material layers, the same homogeneous material can always be used in the further course of the method, so that all material layers comprise the same material.

[0102] As an alternative, two or more materials with different mechanical, electrical, optical, chemical, biological or toxicological properties can be used to form individual or different material layers.

[0103] The material is, for example, a structural material which defines the mechanical properties of the structural element. In addition, the structural material can have other desired properties, such as, for example, electrical properties or thermal properties. In addition to the structural material, there can be a modifiable material in the same layer or in another layer which can be converted particularly well into an electrically conductive material.

[0104] In a first example, the material layer 1 is a plastic layer which comprises a material consisting of plastic or consists of such a material. In addition to plastic, material layers consisting of natural materials, such as, for example, cellulose, are also conceivable in principle.

[0105] The plastic layer can include modified natural materials such as rubber, viscose or cellophane or any industrially produced polymers such as polyimide (PI), polyethylene (PE), polypropylene (PP) and derivatives thereof such as PEI (polyetherimide) etc. Not only material layers consisting of a uniform material are possible, but also chemically uncrosslinked mixtures (Blends) consisting of two or more materials are possible. Other possible materials include chemically crosslinked copolymers such as ABS and composite materials such as GFK, PCB and polymer materials with fillers such as polymers with embedded ceramic particles.

[0106] In a second process step, the material layer 1 is modified in several partial sections. Figure 2 The partial sections can be connected or separated. The partial sections can include any part of the previously applied material layer 1. The partial sections and their sizes can be selected in a targeted manner.

[0107] For example, the layer thickness of the material layer can also be selected in such a way that the desired properties of the layer composite are optimized according to its target parameters. The geometric extension of the material layer can be controlled in the steps of applying and modifying the material. In particular, the individual layers can be applied additively in different forms in the first step. In the second step, the extension of the partial layers along the stacking direction of the material layers can also be changed by modification. As a result, both structural material and modifiable material can be present in one layer.

[0108] In a first example, the modification of a subsection of the material layer 1 is carried out by means of a LIG process. During this process, a restructured sublayer 3 is produced in the material layer 1 in the corresponding subsection. The sublayer 3 differs from the remaining material layers in at least one property. The sublayer 3 differs from the remaining material layer 1, for example, in its electrical conductivity or, for example, in its porosity. Furthermore, as an alternative or in addition, the sublayer 3 can also differ from the remaining material layers in terms of particle size or in terms of carbonization of the material.

[0109] In particular, the structured partial layer is electrically conductive, and the remaining material layer 1 is barely electrically conductive or electrically non-conductive. Furthermore, in particular, the porosity of the structured partial layer 3 is higher than the porosity of the remaining layers. Fig.12 A microscopic picture of a highly porous LIG-modified plastic material of a partial layer 3 is shown in FIG.

[0110] Structuring can be carried out only on the surface of the partial layer 3 , over a portion of the layer thickness or, as shown, over the entire layer thickness.

[0111] During the LIG process, the plastic material is chemically converted by a laser in a thermally induced manner, so that a structure based on an inorganic carbon material is produced. The structured partial layer can, for example, have a material based on graphene, graphite, fullerenes, their (partially) oxidized derivatives, etc.

[0112] Preferably, the (organic) plastic material of the remaining material layer 1 is electrically non-conductive and the material of the structured partial layer 3 is electrically conductive.

[0113] The LIG process can be supported by auxiliary materials, such as suitable catalysts, pre-doping substances in the material layer 1 and reactive groups introduced into the material layer 1. The catalyst can be metal particles, metal salts or metal complexes dispersed in the material layer 1. The pre-doping substances can be carbon materials to be produced and their derivatives. The reactive groups can be short-chain organic molecules with suitable reactive (end) groups, such as, for example, aromatic groups.

[0114] The auxiliary materials mentioned are used in trace amounts. The process is preferably carried out without significant addition of auxiliary materials. The auxiliary materials may in particular already be present in trace amounts in the raw materials used.

[0115] exist Figure 3 In the third step shown, the structured partial layer 3 is post-processed. In this example, for this purpose, an electrically conductive metal such as copper, silver, gold, platinum or palladium is applied to the pores of the partial layer 3 and / or as a thin layer 4 on the surface of the partial layer 3 by means of a suitable method.

[0116] Such suitable methods may be electroplating processes such as, for example, electroplating, electroless plating, adsorption, etc. As an alternative, however, the application may also be carried out, for example, by spraying, infiltration or screen printing.

[0117] The surface treatment Figure 3 Schematically outlined in FIG. 5 by a cover 5, which covers the surface to be post-processed. In particular, this can be a device, by means of which the post-processing of the surface is carried out.

[0118] In an optional step, a seed layer is applied to the surface of the structured partial layer 3 before the described surface treatment, which serves as a basis for the subsequent surface treatment. In particular, such a seed layer can facilitate the application of the metallic material and thereby, for example, simplify and / or accelerate the electroplating process or the screen printing process or the spraying process. The seed layer is, for example, a nanoscale seed layer.

[0119] Then in the fourth step ( Figure 4 ), another material layer 6 is applied to the first material layer 1, and as in Figures 5 to 7 The additional process step, namely the modification of the applied material layer 6 ( Figure 5 ), post-processing of the surface ( Figure 6 ), applying further layers if necessary ( Figure 7 ) is repeated one or more times. Figure 5 As shown in FIG, the partial layers 3 are preferably modified in such a way that a plurality of partial layers of material layers arranged one above the other form a continuous structure.

[0120] Optionally, the material layer 7 can also be as in Figure 7 The material layers shown in the figure do not extend over the entire surface of the underlying material layer. Optionally, the material layers can also be applied side by side.

[0121] exist Figure 8 and Fig. 9 An alternative embodiment is shown in . In this exemplary embodiment, the partial layers are structured partially only on the surface of the material layer and partially over the entire layer thickness.

[0122] The individual structured partial layers of a plurality of adjacent material layers are partially linked or, for example, also form independent structures that are not linked. Figure 8 and Fig. 9 This is shown in . The structure can consist of a single partial layer.

[0123] exist Fig.10 and Fig.11 An exemplary illustration of a finished structural element 10 with a plurality of material layers printed one above the other is shown in FIG. Fig.10 A cross-sectional view is shown.

[0124] Thus, a structural element can be provided, which comprises a plurality of material layers and partial layers 1a to 1f consisting of different materials. For example, 1e and 1f form layers comprising different materials. By means of the method described above, electrically conductive structures can be structured in the structural element. Thus, electrical structural elements can be produced in an additive manner without the need for further post-processing steps. Thus, for example, capacitor elements, such as plate-shaped capacitors, can be produced.

[0125] In a second example, the material layer 1 comprises an organic material into which a ceramic material is embedded. The ceramic material comprises metal elements in its composition. The ceramic material is not further restricted. Then, in a second step of the method, a metallic and electrically conductive structure is produced on selected partial sections of the ceramic layer by targeted sintering of the ceramic material. In addition, a ceramic partial layer that no longer comprises an organic material can be produced.

[0126] In a third example, material layer 1 comprises an organic material in which a metal is embedded, which metal is sintered onto selected partial sections of material layer 1 in a second step of the method in order to produce a metallic partial layer as an electrically conductive structure.

[0127] Between and / or after the aforementioned production steps, auxiliary steps can be present in any desired number and sequence. These are in particular steps of cleaning, washing, rinsing, neutralization, activation, drying, etc. The exact selection and sequence depends on the component to be produced, its desired properties, the materials used, the additive production method used, etc.

[0128] Furthermore, subsequent steps may follow after the application of the last material layer. This may involve, for example, shaping, external metallization, insulation, painting, binder removal and sintering. Here, too, the steps performed depend on the specific component to be produced, its desired properties, the materials used, the additive manufacturing method used, etc.

[0129] The equipment required for the described process can essentially consist of a transport system, such as a robot arm, a conveyor belt and individual processing stations. The components to be constructed can be transported from station to station or a station can be moved to a fixed component to be constructed.

[0130] The method described can be used to produce essentially all conceivable products which consist of additively coatable organic materials or plastics and optionally also of ceramic materials and / or metals and which have any type of electrical contacting.

[0131] Components produced in an additive manner always include an organic material that can be applied in an additive manner and optionally include, for example, embedded ceramic particles and / or metal particles. In addition, the modified partial layers can be reinforced with a metallic surface coating such as, for example, composed of Cu, Pd, Au, Ag, Ni, etc.

[0132] In this way, a plastic component can be produced into which ceramic layers (for the desired functionality) and metallic layers (for example for electrical contacting) are embedded.

[0133] As a result, multilayer components comprising plastic, ceramic and metal can be produced by additive production, ie, for example, by 3D printing, using modified steps.

[0134] Finally, the additively produced green body must be sintered in order to obtain a finished, ready-to-use component.

[0135] Passive electronic components can be produced, for example, preferably in multilayer form and with internal electrodes and with a carrier substrate composed of plastic (such as, for example, PCB, FR4) and / or of ceramic (such as, for example, AlOx or AlN, PZT, PLZT, PCZT, ferrites, varistor ceramics such as ZnO, PTC ceramics, NTC ceramics, LTCC, HTCC).

[0136] In one embodiment, the described method can be used, for example, to produce a layer structure of a capacitor having internal electrodes.

[0137] For this purpose, a material layer made of plastic is provided. Sections of the surface of the plastic layer are modified in such a way that the electrical conductivity is changed compared to the plastic. The electrical conductivity is increased in a targeted manner in order to form electrodes of a capacitor.

[0138] As described above, the modification is carried out in the LIG process by converting the plastic into an electrically conductive carbon derivative. The modified partial layer is then reinforced by electroplating copper and the conductivity is further increased.

[0139] The next plastic layer is then applied to the now existing first material layer.

[0140] This next plastic layer is then likewise modified in order to produce the next electrode layer, etc., until a further plastic layer is applied in the last process step, which is no longer modified. The modification can extend over the entire material layer thickness.

[0141] The sublayers with increased electrical conductivity then form the internal electrodes of the capacitor. The sublayers are arranged in such a way that sublayers of adjacent material layers adjoin one another and form a continuous, uniform electrode structure.

[0142] Such an electrode structure, which forms the internal electrode of the capacitor, then extends perpendicularly to the stacking direction of the material layers. The layer sections with lower conductivity located between them act as separators.

[0143] This results in a structural element which has a first material layer on the bottom side, which is modified only on its top side; which then includes any number of material layers with modifications which form the actual capacitor; and which includes an unmodified plastic layer as a termination layer on the top side.

[0144] As an additional auxiliary step, after providing each material layer, unused raw materials can be recovered and the surface of the resulting material layer can be cleaned. The LIG process is then carried out and then cleaned again. After copper plating, the material layer is neutralized, washed, rinsed and dried.

[0145] If a ceramic-containing plastic material is used for the capacitor, such as ceramic particles embedded in a polymer matrix, for example, steps for removing the binder or for sintering and shaping and hard machining steps such as grinding, for example, can follow to conclude the process.

[0146] To complete the process, after all material layers have been applied, external contacts can be applied to the outer sides of the capacitor by spraying or a similar suitable process, and the remaining surfaces of the capacitor can be coated with a protective lacquer / protective insulation. In addition, the capacitor can also be shaped, ie, for example cut to size, and an additional cover can be applied.

[0147] List of reference numerals:

[0148] 1. First material layer

[0149] 2 Job Board

[0150] 3 Partial Layers

[0151] 4 Thin layer

[0152] 5 Schematic cover for surface treatment

[0153] 6 Another material layer

[0154] 7 Another material layer with smaller size

[0155] 10 Additively produced structural elements

[0156] 1a, 1b, 1c, 1d, 1e, 1f material layers.

Claims

1. Additive production methods, which The following steps are involved: - applying a material layer (1) in an additive manner; - modifying a part of the applied material layer (1) with respect to its properties, so that a partial layer (3) is structured in the material layer (1), wherein the partial layer (3) differs from the remaining material layer at least with respect to the modified properties.

2. The additive production method according to claim 1 , comprising applying a further material layer ( 6 ) in an additive manner and modifying a part of the further material layer ( 6 , 7 ) in terms of properties, thereby structuring a partial layer ( 3 ) in the material layer ( 6 ), in, The partial layer (3) differs from the remaining material layers at least in terms of modified properties.

3. The additive production method according to claim 2, in, The material layer (1) and the further material layer (6) are applied directly one above the other and / or side by side.

4. The additive production method according to any one of claims 1 to 3, in, The material layer (1) is composed of different materials, in particular a structural material and a modifiable material.

5. The additive production method according to any one of claims 1 to 4, in, The material layers (1, 6, 7) include ceramic material or consist of ceramic material or include metal.

6. The additive production method according to claim 5, in, The material layers (1, 6, 7) are made of metal.

7. The additive production method according to claim 5 or claim 6, in, Sintering for structuring the partial layer (3) is carried out in a part of the applied material layer (1, 6, 7).

8. The additive production method according to any one of claims 1 to 7, in, The material layers (1, 6, 7) include plastic or consist of plastic.

9. The additive production method according to claim 8, in, The plastic is resistant to high temperatures.

10. The additive production method according to claim 8 or claim 9, in, In a portion of the applied material layer (1, 6, 7), the plastic is converted into inorganic carbon in order to structure the partial layer (3).

11. The additive production method according to claim 10, in, The partial layer is structured by a thermal process, a thermal method, irradiation by electron beam, laser, UV-VIS radiation, IR radiation or X-ray radiation or microwave radiation.

12. The additive production method according to claim 10 or 11, in, The partial layer is structured by mechanical methods, application of plasma or chemical methods.

13. The additive production method according to claim 10 or 11, in, A laser-induced graphene process is carried out in a part of the applied material layer (1, 6, 7) for structuring the partial layer (3).

14. The additive production method according to claim 13, in, The material layers (1, 6, 7) contain auxiliary materials that support the laser-induced graphene process, such as, in particular, catalysts, predopants or reactive groups.

15. The additive production method according to any one of claims 1 to 14, in, The structured partial layer (3) has at least improved electrical conductivity compared to the remaining material layers, and the additive production method comprises a post-treatment step for surface treatment of the structured partial layer (3) to further improve the electrical conductivity.

16. The additive production method according to claim 15, in, The post-treatment step is carried out before applying the further material layer (6, 7).

17. The additive production method according to any one of claims 15 or 16, in, Before the post-treatment step, a seed layer is applied to the surface of the structured partial layer (3), which seed layer serves as a basis for the subsequent surface treatment.

18. The additive production method according to any one of claims 15 to 17, in, The surface treatment includes the process steps of electroplating, spraying or screen printing.

19. The additive production method according to any one of claims 1 to 18, in, The modified properties are electrical conductivity and / or particle size distribution, and the partial layer has at least an increased electrical conductivity and / or a modified particle size distribution compared to the remaining material layer.

20. The additive production method according to any one of claims 1 to 19, in, The altered property is porosity, and the partial layer has at least an increased porosity compared to the remaining material layer.

21. The additive production method according to claim 19 or claim 20, in, In a post-treatment step, an electrically conductive or catalytically active material is introduced into the pores of the partial layer (3).

22. The additive production method according to any one of claims 1 to 21, in, The application of the material layers (1, 6, 7) is carried out by means of one of the additive methods, namely photopolymerization, material extrusion, material jetting, binder jetting, powder bed fusion, direct energy deposition or lamination.

23. The additive production method according to any one of claims 1 to 22, in, A plurality of partial layers (3) of the material layers (1, 6) are structured in one step.

24. The additive production method according to any one of claims 1 to 23, in, The partial layer is structured only on the surface of the material layer, or the partial layer (3) is structured over the entire layer thickness of the material layer (1, 6).

25. The additive production method according to any one of claims 1 to 24, in, The structural element (10) is formed from a plurality of material layers (1, 6, 7, 1a-1f), wherein partial layers (3) are structured in a plurality of the material layers and no structured partial layer (3) is formed in at least one material layer (7).

26. The additive production method according to claim 25, in, The structured partial layer (3) is arranged in such a way that it forms an internal electrode in the component.

27. The additive production method according to any one of claims 25 or 26, in, In a further method step, the applied and modified material layers (1, 6, 7, 1a-1f) of the component (10) are freed of binder and sintered.

28. The additive production method according to any one of claims 25 to 27, in, To produce the component (10), further production steps follow, such as, in particular, shaping, external metallization, insulation, painting, binder removal and sintering, wherein the production steps are carried out successively or simultaneously.

29. Electrical component (10) produced according to the method of claims 1 to 28 and comprising a plurality of material layers (1, 6, 7, 1a-1f), in, A plurality of the material layers include structured partial layers (3) having increased electrical conductivity or increased porosity or a changed particle size distribution, and no structured partial layer (3) is formed in at least one material layer (7).

30. The electrical component (10) according to claim 29, which is designed as a capacitor.

31. A device for carrying out a process according to claims 1 to 28 for producing a structural element (10) according to claim 29 or 30, comprising a transport system and individual processing stations at which the steps of the process are carried out, in, The transport system is designed in such a way that, in an operating state, the structural element (10) can be transported from one workstation to another, or the workstation can be moved to the structural element (10).

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