Additive manufacturing method involving modification of a partial layer

Abstract

The present invention relates to an additive manufacturing method, - a step of applying a material layer (1) additively, - a step of modifying the properties of a portion of the applied material layer (1) such that sub-layers (3) within the material layer (1) are structured, wherein the sub-layers (3) differ from the remaining material layer at least in the modified properties, and furthermore the present invention relates to correspondingly manufactured parts and suitable manufacturing equipment.

Description

Technical Field

[0001] The present invention relates to an additive manufacturing method for modifying a partial layer within a component.

Background Art

[0002] In the prior art, numerous additive manufacturing methods are known. Additive manufacturing methods enable the structured construction of components without material loss due to subsequent processing, even for components having a special shape. The shaping of the component is carried out during manufacturing.

[0003] Nevertheless, in the prior art, components having certain components are restricted in additive manufacturing, difficult, or even impossible. For example, electronic components and catalytically active components are still separately attached within or on the component and cannot be printed during the additive manufacturing process.

[0004] In particular, an exemplary method for applying and modifying a conductive component on a 2D substrate is the application of the substrate material and subsequent modification by a laser-induced graphene process, which is known, for example, from US2020 / 0112026A1, US2020 / 0348121A1, CN111879341A, or WO2018 / 085789A1.

[0005] The conductivity of the modified LIG material can be further enhanced in a post-treatment step, as shown in CN109440145A, US2018 / 0199441A1, and WO2020 / 197606A2.

[0006] Also, US2021 / 0395420A and WO2017 / 051182A1 disclose high-temperature resistant materials in the art.

[0007] CN114322741A shows an example of a method for manufacturing a ceramic film sensor. For this purpose, a metal part is provided as a substrate, and a precursor layer of a ceramic insulating film is applied, for example, by screen printing. However, in this method, it is not possible to structure a partial layer of the already printed layer.

[0008] DE102019101268A1 discloses a process for the production and modification of silicon carbide-containing objects.

[0009] WO2017 / 176251A1 shows a printing method in which a liquid ink is used as a vehicle and a photosensitive additive is distributed over a part of a polymer layer to which it has been previously applied.

[0010] US2018 / 0129002A1 discloses various possible post-treatment steps for the surface treatment of additively manufactured electrical components.

[0011] Finally, US9,827,713B1 and WO2020 / 236455A1 disclose special devices for 3D printing having a plurality of processing stations at which individual steps of a printing process are performed.

[0012] US9,827,713B1 shows a robotic arm that immerses a substrate in various resins at a plurality of stations to form various layers of a part.

[0013] In WO2020 / 236455A1, a plurality of plates are melted successively to form layers of a part.

Summary of the Invention

[0014] One object of the present application is to provide a method, parts and equipment that overcome the disadvantages of the prior art.

[0015] The present invention relates to an additive manufacturing process comprising several steps. In a first step, a material layer is applied additively. This layer can be applied, for example, to a build plate provided therefor or to a layer previously applied additively. This layer can comprise any material suitable for additive manufacturing or 3D printing.

[0016] In a further step, at least a part of the previously applied material layer is modified in certain properties, and thus a sublayer is structured in the material layer. A partial region of the material layer can here be referred to as a sublayer. The sublayer differs from the remaining material layer outside the modified part of the layer in at least one property of the material. In one embodiment, the entire material layer is modified.

[0017] During the modification, in particular, the chemical, physical, morphological and / or structural properties of the material layer can be changed. Among other things, in various embodiments of the present invention, the conductivity, porosity or particle size of the material layer is changed, or an organic material is carbonized into an inorganic carbon material.

[0018] For example, a part of the applied material layer is modified such that the conductivity of that part of the layer changes, and thus a sublayer is structured whose conductivity deviates from that of the remaining material layer.

[0019] During the modification, several properties of the material layer can be changed by the modification step. For example, the sublayer structured after the modification can differ from the remaining material layer in terms of its conductivity, porosity or particle size.

[0020] According to the described method, a layer structure with various desired properties can be generated without printing separate layers. Furthermore, since the properties of the printed material layer can already be adjusted during the additive manufacturing process, the corresponding post-treatment steps can be omitted.

[0021] Changing the properties of the previously additively manufactured layers as desired enables the additive manufacturing of parts having properties that cannot be manufactured in existing additive manufacturing processes. Such properties include, in particular, the properties mentioned above, conductivity, particle size, porosity, and other equivalent material properties.

[0022] After the application and modification of the material layer, in a further method step, a further material layer can be applied and at least one material property of a part of the layer is changed, such that a partial layer is structured whose material property deviates from the conductivity of the remaining material layer. Alternatively, a material layer can be applied whose partial layer is not changed.

[0023] In particular, the partial layer can be structured such that it coincides with a partial layer within the first material layer and both partial layers form a continuous layer (zusammenhaengende Schicht) having, for example, homogeneous properties.

[0024] In particular, in one embodiment, the same conductivity is set for the partial layer and a further partial layer. In this way, conductive layers, for example internal electrodes, can be structured in non-conductive materials.

[0025] In one embodiment, the material layer and the further material layer are applied directly one above the other or directly adjacent to each other. In a further embodiment, the material layers can be applied adjacent to each other and further one above the other.

[0026] The material layer can consist of different materials, in particular a structural material and a modifiable material.

[0027] The different materials are applied, in particular, in several steps of a printing process. The structural material does not lend itself to the described modification steps but provides the desired structure for the part to be manufactured.

[0028] The modifiable material is suitable for modification during the modification step. By being able to modify a part of the modifiable material, a structure having the desired properties can be generated.

[0029] The material that can be modified is preferably a high-temperature resistant material that can be 3D printed using a bath-based photo polymerization method, such as the plastic class of ThermoBlast or DL-400.

[0030] If the material can withstand an ambient temperature of at least 300 °C, it can be regarded as "high-temperature resistant". Therefore, the melting point or decomposition point (der Schmelz- bzw. Zersetzungspunkt eines hochtemperaturfesten Materials) of the high-temperature resistant material is 300 °C or higher, and the structure of the high-temperature resistant material does not change at temperatures up to 300 °C.

[0031] For example, it can be an internal electrode or an active layer within the material layer. The remaining unmodified material layers continue to contribute to the overall structure of the component.

[0032] In one embodiment, the material layer or a further material layer comprises a ceramic material.

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

[0034] In a part of the applied material layer, the layer material is modified by sintering, and thus the structuring of the partial layer is carried out. The partial layer can, for example, comprise or be composed of a metallic material or a ceramic material.

[0035] By means of targeted, spatially resolved sintering (Gezieltes, ortsaufgeloestes Sintern), the structuring of specific partial layers with desired properties becomes possible. For example, the ceramic material can be modified during sintering so that a conductive metal partial layer is formed in the ceramic layer. An organic material having metal or ceramic inclusions can be modified, for example, such that the organic component is removed and a metal or ceramic partial layer is formed that consists mainly of or is composed of such a material.

[0036] Furthermore, sintering also changes the porosity of the partial layer. In particular, a structure with larger pores can be formed. By modifying the pores, for example, the suitability of the material as a catalyst, carrier material, or filter unit can be adjusted.

[0037] In a further embodiment, the material layer or a further material layer comprises or consists of an organic material. In the organic material, particularly in plastics, preferably, a ceramic material and / or a metal material that can be modified as described above are further incorporated.

[0038] Preferably, the material layer or a further material layer comprises or consists of plastic.

[0039] Also, natural materials such as cellulose-based materials, and modified natural materials such as rubber, viscose, and cellophane can be used as organic materials.

[0040] Various plastics can be used. In particular, a homogeneous material layer made from a uniform base material is preferred. Possible materials include PI, PEI, PE, PP, etc.

[0041] Furthermore, blends, i.e., non-chemically cross-linked mixtures made from two pure plastic materials or chemically cross-linked copolymers such as ABS, are also conceivable. In a further embodiment, the material of the material layer also includes composite materials such as GSK or PCB, or a polymer material filled with fillers such as ceramic particles or metal particles, for example.

[0042] In one embodiment, in the plastic material, the partial layer can be structured by converting the plastic into inorganic carbon.

[0043] Particularly preferably, the laser-induced graphene process can be applied, and it is a high-temperature resistant plastic that is 3D printed by bath-based photopolymerization in particular. In particular, the high-temperature resistant plastic is suitable for the use of the LIG process due to its chemical composition and processability at high temperatures. Here, it is possible to convert an organic material into a desired graphene or graphite structure of carbon by a laser.

[0044] The plastic composition preferably contains at least one monomolecular or oligomeric chemical species, each of which contains at least one carbon-carbon double bond that can be polymerized by radical polymerization, and the monomolecular or oligomeric chemical species is present in a total amount of 25 to 99% by weight based on the plastic composition.

[0045] Preferably, the plastic composition further contains at least one photoinitiator, particularly preferably a titanocene photoinitiator, and this photoinitiator is preferably present in a total amount of 0.1 to 15% by weight, and further contains at least one coinitiator, particularly preferably a thiol coinitiator, and is preferably present in a total amount of 0.5 to 20% by weight.

[0046] Alternatively, the plastic composition includes a thermosetting component A containing one or more chemical species selected from the group consisting of monomers and / or oligomers and / or prepolymers of maleimide derivatives and their isomers as shown in (Chemical Formula 1): n is an integer from 1 to 10, R1 represents H, CH3 or CH2, and R2 independently represents a linear, branched or cyclic aliphatic or aromatic C5-C40 group from one or more of the group of phenyl, benzyl, phenethyl, methyl, ethyl, propyl, butyl, pentyl, hexyl, octyl, decanyl, dodecanyl, acetic acid, propanoic acid, butanoic acid, pentanoic acid, undecanoic acid, dodecanoic acid, benzoic acid and corresponding esters, alkyl esters or aromatic esters, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, adamantyl, isobornyl, propenyl, biphenyl, naphthyl, anthracenyl, pyrenyl, bis(methylene)oxy, bis(ethylene)oxy, bis(phenyl)methane, bis(phenyl)ethane, bis(phenyl)propane, bis(phenyl)butane, bis(phenyl)ether, bis(phenyl)thioether, bis(phenyl)amino, or bis(phenyl)sulfone. [Chemical Formula]

[0047] Furthermore, the plastic composition further includes a photocurable component B having one or more chemical species selected from the group consisting of (meth)acrylate, (meth)acrylamide, vinyl ester, vinyl ether, vinyl, allyl, alkynyl or styrene compounds and their derivatives, which are substituted with at least one molecule from the group where component A is selected. The amount of component A ranges from 30 wt% to 95 wt% based on the total weight of components A and B, and the amount of the photocurable component B ranges from 5 wt% to 70 wt% based on the total weight of components A and B.

[0048] Particularly preferably, component A includes a species of component A in which n is an integer from 2 to 10 and which has an aromatic group bonded to the N atom of the maleimide ring in (Chemical Formula 1), preferably via a methylene group, and the amount thereof is 20% by weight to 100% by weight, preferably 30% by weight to 100% by weight, more preferably 40% by weight to 100% by weight based on the total weight of component A.

[0049] The partial layer in the plastic can be modified by an appropriate method, and can particularly be converted to inorganic carbon. Examples of such appropriate methods include thermal methods, mechanical methods such as grinding or roughening or ultrasonic processes, use of plasma, irradiation by, for example, electron emission, laser, UV-VIS radiation, IR radiation or X-ray radiation, microwave radiation, and chemical processes such as etching or chemical activation of the surface.

[0050] For example, the partial layer in the plastic can be structured using a laser-induced graphene process. In the laser-induced graphene process, also known as the LIG process, the material being treated is chemically and / or physically excited and changed by the effect of the laser radiation at the point of energy impact. In particular, thermal conversion or decomposition occurs at the impact point.

[0051] Specifically, in the LIG process, the organic carbon of the plastic is converted (''carbonized'') to inorganic carbon modifications such as graphene, graphite, fullerenes, etc. by a desired energy input using laser radiation. Therefore, the LIG process is generally not limited to the specific conversion of carbon to graphene, but can also include the conversion of carbon to other inorganic modifications.

[0052] In particular, a conductive carbon structure can be formed in the material layer. Furthermore, the aforementioned inorganic carbon decorations also differ, for example, in terms of porosity and crystallinity.

[0053] In particular, by means of the LIG process, it is possible to apply a modification to the surface of the material layer as desired, or to penetrate deep into the material layer and, depending on the conditions, apply a modification that includes the entire thickness of the sublayer.

[0054] In one embodiment, the material layer comprises auxiliaries (Hilfsstoffe) that assist the laser-induced graphene process, in particular catalysts, predopants or reactive groups.

[0055] For example, metal particles, metal salts or metal complexes dispersed in the layer can be used as catalysts. In particular, the carbon materials and their derivatives produced can be used as predopants.

[0056] In various embodiments, short-chain organic molecules having suitable reactive (terminal) groups, such as aromatic compounds, are used as reactive groups.

[0057] The auxiliaries described are preferably used in trace amounts. Preferably, the process is carried out without explicitly adding the auxiliaries. In particular, the auxiliaries may already be present in trace amounts in the raw materials used.

[0058] In one embodiment of the method, a post-treatment step is performed on the structured sublayer in order to further modify the properties of the sublayer and, in particular, to enhance the properties set by the modification. Preferably, for this purpose, a surface treatment is carried out on the structured sublayer at the surface of the material layer.

[0059] During the additive manufacturing process, the desired properties of the manufactured part can already be set.

[0060] In one embodiment where the structured sublayer has at least increased conductivity compared to the remaining material layer, possible post-treatment steps include surface treatment of the structured sublayer to further increase its conductivity.

[0061] For example, surface treatment includes processes such as plating, sputtering, screen printing, or partial steps thereof. However, the surface treatment is not limited to the aforementioned processes. In particular, a metal surface coating having high electrical conductivity can be applied using the aforementioned processes. In this way, the conductivity of the sublayer can be significantly increased.

[0062] A further surface treatment option is the application of a catalyst to improve the catalytic properties of the modifying material. In this context, the catalyst is any form of catalytically active material that can be applied, for example, in powder form. In particular, the catalyst can be applied to the surface of the modifying material or introduced into the pores.

[0063] In any step, in one embodiment, a seed layer is applied to the surface of the structured sublayer prior to one of the aforementioned surface treatment steps, and this seed layer serves as the basis for subsequent surface treatment. In particular, such a seed layer facilitates the application of a metal material and thus can simplify and / or accelerate, for example, a plating process or a screen printing process or a sputtering process. In particular, the seed layer can be a nanoscale seed layer.

[0064] In some embodiments, the structured sublayer has at least enhanced porosity compared to the remaining material layers.

[0065] In an optional post-treatment step, a conductive material can be introduced into the pores of the structured sublayer to increase the conductivity of the material.

[0066] Preferably, in an embodiment, the post-treatment step is carried out before applying a further material layer. In this way, the individual material layers can be modified separately as desired, or the modified properties can be improved.

[0067] The additive manufacturing process itself, i.e., the additive application of material layers (3D printing), can be carried out using any suitable manufacturing process such as vat photopolymerization, material extrusion, material jetting, binder jetting, powder bed fusion, direct energy deposition, or sheet lamination.

[0068] Due to its high precision, the vat photopolymerization process is particularly suitable for the process described here.

[0069] In one embodiment, a plurality of sub-layers within a material layer are structured in one step. To that end, for example, a plurality of lasers are irradiated onto the material layer in order to carry out a plurality of LIG processes in parallel. Similarly, a plurality of sintering processes or similar modification steps can be carried out in parallel on a plurality of parts of the material layer.

[0070] In this method, the part is preferably formed from several material layers, and sub-layers are structured in each of the plurality of material layers as described above.

[0071] Preferably, at least one material layer does not have structured sub-layers formed therein. Such a material layer can in particular consist of a structural material. The structural material can be a material that is not modifiable. Such a layer can, for example, increase the stability of the components or define the structure of the part.

[0072] The structured sub-layers can be arranged optionally or in a specific system. In one embodiment, the structured sub-layers are arranged such that a plurality of sub-layers of adjacent material layers are adjacent to each other. For example, a plurality of conductive modification sub-layers can be adjacent to each other such that internal electrodes are formed in the part.

[0073] In an embodiment of the manufacturing step, auxiliary steps of any number and order can be carried out during and / or after the aforementioned manufacturing steps. In particular, this can include steps such as cleaning (Reinigen), washing (Waschen), rinsing, neutralizing, activating, drying, etc. The exact selection and order will vary, for example, depending on the part being manufactured, its desired properties, the materials used, or the additive manufacturing method employed.

[0074] In particular, when an applied and modified material layer exists as a green layer, debinding and sintering steps may follow.

[0075] Furthermore, in an embodiment of the manufacturing method, after the last layer of material has been applied, additional, usually final steps may follow. These include, for example, packaging (Konfektionierung), external metallization, insulation, painting, debinding, sintering, etc. The specific steps are preferably based on the part to be manufactured, its desired properties, the materials used, or the additive manufacturing method employed. These steps can be carried out either continuously or simultaneously.

[0076] The present invention is also directed to electrical components manufactured according to the described method. Such components can have all the characteristics described above during the process of the method.

[0077] In one embodiment, the component comprises a plurality of material layers, and a plurality of the material layers among them comprise structured sub-layers having enhanced conductivity. In a preferred embodiment, at least one material layer does not have a structured sub-layer formed therein.

[0078] In particular, the electrical component can be designed as an electrical capacitor, for example, a flat capacitor. The plates of the capacitor are preferably arranged perpendicular to the stacking direction of the additive manufacturing method. The internal electrodes of the capacitor are formed by a plurality of adjacent modified sub-layers having enhanced conductivity. Between them, each material layer has a non-modified portion with low or no conductivity.

[0079] The present invention is also directed to a device for carrying out the described process for manufacturing parts. This device comprises at least one transport system and individual processing stations for performing the steps of the process. And the transport system is designed such that, in the operating state, it can transport parts from station to station or the stations can move to the parts. In this way, all the processing steps of the method can be carried out by one device.

[0080] Hereinafter, the present invention will be described in more detail with reference to embodiments and related drawings. It should be noted that the present invention is not limited to the embodiments shown in the following figures.

Brief Description of the Drawings

[0081]

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DETAILED DESCRIPTION OF THE INVENTION

[0082] Elements that appear similar or identical in the figures are assigned the same reference numerals. The drawings and the ratios in the figures are not to scale.

[0083] FIGS. 1 to 7 schematically show an exemplary additive manufacturing process. In the first step shown in FIG. 1, material layer 1 is applied to work plate 2. Material layer 1 is applied using a suitable additive process. Here, examples of suitable additive processes include Vat Photopolymerization (VPP), Material Extrusion (MEX), Material Jetting (MJT), Binder Jetting (BJT), Powder Bed Fusion (PBF), Direct Energy Deposition (DED), and Sheet Lamination (SHL). The VPP method is preferred because of its particularly high printing accuracy. Other common additive methods can also be used.

[0084] For example, material layer 1 consists of a single homogeneous material. When constructing other material layers, all material layers are composed of the same material by always using the same homogeneous material.

[0085] Alternatively, one or different material layers can be constructed using two or more materials having different mechanical, electrical, optical, chemical, biological, and toxicological properties.

[0086] The material is, for example, a structural material that defines the mechanical properties of a component. The structural material can also have other desired properties, such as electrical or thermal properties. In addition to the structural material, a modifiable material that can be particularly well converted into a conductive material may be present in the same layer or another layer.

[0087] In the first embodiment, the material layer 1 is a plastic layer that includes or consists of a plastic material. In addition to plastics, material layers made of natural materials such as cellulose are also conceivable.

[0088] The plastic layer can include any industrially produced polymer such as modified natural materials like rubber, viscose, cellophane, and their derivatives such as polyimide (PI), polyethylene (PE), polypropylene (PP), and PEI. Both a material layer made of a uniform material and a chemical blend of two or more non-crosslinked materials are possible. Other possible materials include chemically crosslinked copolymers such as ABS, composite materials such as GFK, PCB, and polymer materials containing fillers such as polymers with embedded ceramic particles.

[0089] In the second process step, a partial section of the material layer 1 is modified. The modified layer is shown in FIG. 2. The partial sections can be contiguous or separated. The partial sections can include any part of the previously applied material layer 1. The partial sections and their dimensions can be selected as desired.

[0090] For example, the layer thickness of the material layer can also be selected so that the desired properties of the layer composite are optimized to a target value. The geometric spread of the material layer can be controlled in the material application and modification steps. In particular, the individual layers can be applied additively in different forms in the first step. In the second step, the spread of the sublayers in the stacking direction of the material layer can also be changed by modification. Thus, both the structural material and the modifiable material can be present in one plane.

[0091] In the first embodiment, the modification of the partial section of the material layer 1 is performed by the LIG process. During this process, a partial layer 3 reconfigured within the material layer 1 is generated in the corresponding partial section. The partial layer 3 is different from the rest of the material layer in at least one property. For example, the partial layer 3 is different from the remaining material layer 1 in terms of conductivity or, for example, porosity. Further, the partial layer 3 may alternatively or additionally be different from the remaining material layer in terms of particle size or carbonization of the material.

[0092] In particular, the structured partial layer is conductive, and the remaining material layer 1 is hardly conductive or non-conductive. In particular, the porosity of the structured partial layer 3 is higher than that of the remaining layer. A microscopic image of the highly porous LIG-modified plastic material of the partial layer 3 is shown in FIG. 12.

[0093] The structuring can be applied only to the surface of the partial layer 3, to a part of the layer thickness, or to the entire layer thickness as shown.

[0094] During the LIG process, the plastic material is thermally induced by a laser and chemically converted, resulting in the formation of a structure based on an inorganic carbon material. The structured partial layer can have a material based on, for example, graphene, graphite, fullerene, (partially) oxidized derivatives thereof, and the like.

[0095] 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 conductive.

[0096] The LIG process can be assisted by auxiliaries such as a suitable catalyst, a predopant to 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 predopant can in particular be the carbon material and its derivatives to be produced. The reactive groups can be short-chain organic molecules having suitable reactive (terminal) groups such as aromatic compounds.

[0097] The above auxiliary agents are used in trace amounts. Preferably, the process is carried out without explicitly adding the auxiliary agents. In particular, the auxiliary agents can already be present in trace amounts in the raw materials used.

[0098] In the third step shown in FIG. 3, the structured partial layer 3 is post-treated. In this embodiment, a conductive metal such as copper, silver, gold, platinum or palladium is applied as a thin layer 4 into the pores of the partial layer 3 and / or on the surface of the partial layer 3 using a suitable method.

[0099] Such a suitable method can be a galvanic process such as electroplating, electroless plating, adsorption, etc. Alternatively, coating by sputtering, infiltration, screen printing, etc. is also possible.

[0100] The surface treatment is schematically shown in FIG. 3 by a cap 5 covering the surface to be post-treated. This can in particular be the equipment for carrying out the surface post-treatment.

[0101] In any step, before the above surface treatment, a seed layer on which subsequent surface treatment is based is applied onto the surface of the structured partial layer 3. In particular, such a seed layer is advantageous for the application of a metal material and can thus facilitate and / or accelerate, for example, an electroplating process, a screen printing process, or a sputtering process. For example, the seed layer is a nano-scale seed layer.

[0102] Thereafter, in the fourth step shown in FIG. 4, a further material layer 6 is applied to the first material layer 1, and further process steps of modifying the applied material layer 6 (FIG. 5), post-treating the surface (FIG. 6), and applying further layers as required (FIG. 7) are repeated one or more times. As shown in FIG. 5, the partial layer 3 is preferably modified such that a plurality of partial layers of the material layers arranged one above the other form a continuous structure.

[0103] Optionally, as shown in FIG. 7, the material layer 7 may not extend over the entire surface of the underlying material layer. The material layers may optionally also be applied adjacent to each other.

[0104] FIGS. 8 and 9 show alternative embodiments. In this embodiment, the sublayers are structured partly only on the surface of the material layer and partly over the entire layer thickness.

[0105] The individual structured sublayers of a plurality of adjacent material layers are partly continuous or form, for example, independent structures that are not continuous. This is also shown in FIGS. 8 and 9. The structure can also include individual sublayers.

[0106] Exemplary representations of a finished part 10 having a plurality of material layers printed one on top of the other are shown in FIGS. 10 and 11. FIG. 10 is a cross-sectional view.

[0107] In this way, parts can be manufactured that include a number of material layers and sublayers 1a - 1f made of different materials. For example, 1e and 1f form layers made of different materials. Using the method described above, conductive structures can be configured within the part. Thus, it means that electrical components can be manufactured additively without the need for further post-processing steps. For example, capacitor elements, such as planar capacitors, can be manufactured in this way.

[0108] In a second example, the material layer 1 includes an organic material in which a ceramic material is embedded. The ceramic material includes a metal element in its composition. The ceramic material is not particularly limited. In a second step, by sintering the ceramic material as desired, metal and conductive structures are generated in selected subsections of the ceramic layer. Furthermore, ceramic sublayers that do not contain an organic material can also be generated.

[0109] In the third embodiment, the material layer 1 comprises an organic material in which a metal is embedded, and this metal is sintered in a selected partial portion of the material layer 1 in the second step of the method in order to produce a metallic partial layer as the conductive structure.

[0110] During and / or after the manufacturing steps described above, there may be any number and order of auxiliary steps. In particular, steps such as cleaning (Reinigen), washing (Waschen), rinsing, neutralization, activation, drying, etc. may be mentioned. The exact selection and order depend on the part to be manufactured, its desired properties, the materials used, the additive manufacturing method used, etc.

[0111] Furthermore, a final step may be carried out after the last material layer has been applied. This includes, for example, packaging (Konfektionierung), external metallization, insulation, painting, debinding (Entbindern), sintering, etc. Here too, the steps to be carried out depend on the specific part to be manufactured, its desired properties, the materials used, the additive manufacturing process used, etc.

[0112] The equipment required for the described process can essentially be composed of a transport system such as a robotic arm or a conveyor belt, and individual processing stations. The parts to be assembled can be transported from station to station or the stations can be moved to the fixed parts to be assembled.

[0113] Essentially, all possible products composed of an additively applied organic material or plastic, and optionally further ceramic materials and / or metals, and having some type of electrical contact, can be manufactured using the method described.

[0114] Parts manufactured additively are always composed of an additively applied organic material and optionally, for example, embedded ceramic particles and / or metal particles. The modified partial layer can also be reinforced with a metal surface coating such as Cu, Pd, Au, Ag, Ni, etc.

[0115] Thus, it is possible to manufacture plastic parts embedded with a ceramic layer that realizes desired functionality or a metal layer for electrical contacts, etc.

[0116] That is, a multilayer part including plastic, ceramic, and metal can be manufactured through a modification step by additive manufacturing such as 3D printing.

[0117] In order to obtain a ready-to-use part immediately after completion, it is necessary to sinter the additively manufactured green body.

[0118] For example, passive electronic components, preferably multilayer, having internal electrodes, and passive electronic components having a carrier substrate made of plastic such as PCB, FR4 and / or ceramics such as AlOx or AlN, PZT, PLZT, PCZT, ferrite, ZnO varistor ceramics, PTC ceramics, NTC ceramics, LTCC, HTCC can be manufactured.

[0119] In one embodiment, the described method can be used, for example, to manufacture a layered structure of a capacitor having internal electrodes.

[0120] Furthermore, a material layer made of plastic is provided. A partial section of the surface of the plastic layer is modified so that its conductivity changes compared to the plastic. The conductivity is increased as desired to form the electrodes of the capacitor.

[0121] The modification is carried out by converting the plastic into a conductive carbon derivative by the LIG process as described above. The modified partial layer is reinforced by electroplating with copper, and its conductivity is further increased.

[0122] Thereafter, the next plastic layer is applied above the already existing first or initial material layer.

[0123] This is similarly modified to form the next electrode layer and continues until a further plastic layer is applied in the final process step and is not modified any further. The modification can extend across the entire thickness of the material layer.

[0124] Thereafter, a sub-layer having improved conductivity forms the internal electrodes of the capacitor. The sub-layers are arranged such that the sub-layers of adjacent material layers are adjacent to each other to form a continuous and uniform electrode structure.

[0125] Such an electrode structure forming the internal electrodes of the capacitor extends perpendicular to the stacking direction of the material layers. The layer sections having lower conductivity therebetween function as separators.

[0126] Thus, a component is obtained that has a first material layer on the bottom surface, only the top surface of which is modified, followed by any number of modified material layers that form the actual capacitor, and has an unmodified plastic layer as the final layer on the top surface.

[0127] As an additional auxiliary step, after each material layer is prepared, the unused raw material can be returned and the surface of the produced material layer can be cleaned. Thereafter, the LIG process is carried out and it is cleaned again. After galvanic copper plating, the material layer is neutralized, washed, rinsed, and dried.

[0128] When a ceramic-containing plastic material such as ceramic particles embedded in a polymer matrix is used for the capacitor, after the debinding or sintering and shaping steps, hard processing steps such as grinding may follow at the end of the process.

[0129] At the end of the process, after all the material layers have been applied, external contacts can be applied to the outside of the capacitor by sputtering or a similar suitable process, and the remaining surface of the capacitor can be coated with a protective coating / insulation. Further, the capacitor can be cut to a suitable size and packaged, for example, and an additional housing can also be attached.

Explanation of Symbols

[0130] 1 First material layer (Erste Materialschicht) 2 Working plate (Arbeitsplatte) 3 Sub - layers (Teilschichten) 4 Thin layer (Duennschicht) 5 Schematic cap for surface treatment (Schematische Kappe zur Oberflaechenbehandlung) 6 Further material layer (Weitere Materialschicht) 7 Further material layer with smaller dimensions (Weitere Materialschicht mit geringerer Abmessung) 10 Additively manufactured component (Additiv gefertigtes Bauelement) 1a, 1b, 1c, 1d, 1e, 1f Material layers (Materialschichten)

Claims

1. An additive manufacturing method, comprising: - a step of additively applying a material layer (1); - a step of modifying the properties of a portion of the applied material layer (1) such that a sub-layer (3) is structured within the material layer (1), wherein the sub-layer (3) is different from the remaining material layer at least in the modified properties; a method including the above steps.

2. a step of additively applying a further material layer (6) and a step of modifying the properties of a portion of the further material layer (6) such that a sub-layer (3) is structured within the material layer (6), wherein the sub-layer (3) is different from the remaining material layer at least in the modified properties; a method according to Claim 1, including the above steps.

3. The material layer (1) and the further material layer (6) are applied directly on top of and / or adjacent to each other; a method according to Claim 2.

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

5. The material layer (1, 6, 7) contains or consists of a ceramic material or contains a metal; a method according to any one of Claims 1 to 4.

6. The material layer (1, 6, 7) consists of a metal; a method according to Claim 5.

7. In a portion of the applied material layer (1, 6, 7), sintering for structuring the sub-layer (3) is performed; a method according to Claim 5 or 6.

8. The material layer (1, 6, 7) contains or consists of a plastic; a method according to any one of Claims 1 to 7.

9. The plastic is heat-resistant; a method according to Claim 8.

10. For structuring the sub-layer (3), in a portion of the applied material layer (1, 6, 7), the plastic is converted into an inorganic plastic; a method according to Claim 8 or 9.

11. The sub-layer is structured by irradiation with a thermal process, a thermal method, an electron beam, a laser, a UV-VIS beam, an IR beam, or an X-ray radiation or a microwave beam; a method according to Claim 10.

12. The sub-layer is structured by a mechanical method, application of plasma, or a chemical method; a method according to Claim 10 or 11.

13. In the portion of the applied material layer (1, 6, 7), a laser-induced graphene process is performed to structure the sublayer (3). The method according to claim 10 or 11.

14. The material layer (1, 6, 7) contains an auxiliary agent that assists the laser-induced graphene process, such as a catalyst, a predopant, or a reactive group, in particular. The method according to claim 13.

15. The structured sublayer (3) has at least one higher conductivity compared to the remaining material layer. The method includes a post-treatment step of treating the surface of the structured sublayer to further increase the conductivity. The method according to any one of claims 1 to 14.

16. The post-treatment step is performed before the step of applying the further material layer (6, 7). The method according to claim 15.

17. Before the post-treatment step, a seed layer that functions as a base for subsequent surface treatment is applied to the surface of the structured sublayer (3). The method according to claim 15 or 16.

18. The surface treatment includes a process step of electroplating, sputtering, or screen printing. The method according to any one of claims 15 to 17.

19. The modified characteristics are conductivity and / or particle size distribution. The sublayer has a higher conductivity and / or a changed particle size distribution compared to the remaining material layer. The method according to any one of claims 1 to 18.

20. The modified characteristic is porosity. The sublayer has a higher porosity compared to the remaining material layer. The method according to any one of claims 1 to 18.

21. In the post-treatment step, a conductive material or a catalytically active material is introduced into the pores of the sublayer (3). The method according to claim 19 or 20.

22. The application of the material layer (1, 6, 7) is performed by one of the additive methods of VAT photopolymerization, material extrusion, material injection, binder injection, powder bed melting, direct energy deposition, or sheet lamination. The method according to any one of claims 1 to 21.

23. A plurality of the sublayers (3) are structured in one step within the material layer (1, 6). The method according to any one of claims 1 to 22.

24. The sublayer is structured only on the surface of the material layer, or The sublayer (3) is structured through the total layer thickness of the material layer (1, 6). The method according to any one of claims 1 to 23.

25. A component (10) is formed from a plurality of said material layers (1, 6, 7, 1a - 1f), the sub - layer (3) is structured in a plurality of said material layers (7), and the structured sub - layer (3) is not formed in at least one of said material layers (7), The method according to any one of claims 1 to 24.

26. The structured sub - layer (3) is arranged to form internal electrodes within the component. The method according to claim 25.

27. The applied and modified material layers (1, 6, 7, 1a - 1f) of the component (10) are debound and sintered in a further method step. The method according to claim 25 or 26.

28. To manufacture a component (10), a plurality of further manufacturing steps follow, in particular packaging, external metallization, insulation, painting, debinding and sintering, The plurality of manufacturing steps are carried out continuously or simultaneously. The method according to any one of claims 25 to 27.

29. An electrical component manufactured by the method according to any one of claims 1 to 28, having a plurality of material layers, wherein the plurality of said material layers include a structured sub - layer (3) having enhanced conductivity or enhanced porosity or a changed particle size distribution, and at least one of the plurality of said material layers (7) does not have a structured sub - layer (3) formed therein, Electrical component.

30. Designed as an electrical capacitor, The electrical component according to claim 29.

31. Apparatus for carrying out a process according to the method according to any one of claims 1 to 28 for manufacturing a component (10) according to claim 29 or 30, a transport system, and individual processing stations for performing the steps of the process, wherein the transport system is designed such that in the operating state, the component (10) can be transported from station to station or the stations can move to the component (10), Apparatus.

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