Method and apparatus for producing a three-dimensional shaped object by means of layer-by-layer material application

Abstract

Method for producing a three-dimensional molded object (2) by layer-by-layer material application, wherein geometric data for the molded object (2), a carrier part (3) with a base surface (4) for receiving the three-dimensional molded object (2), and a first and a different flowable second material (6, 8) are provided, wherein portions (10) of the flowable first material (6) are applied to the base surface (4) and / or a solidified material layer of the three-dimensional molded object (2) located thereon, according to the geometric data, using at least one nozzle to produce at least one material layer (14A, 14B, 14') of the three-dimensional molded object (2), wherein the at least one material layer (14A, 14B, 14') consisting of the flowable first material (6) is solidified, and a transfer body (18) is provided.a surface area of ​​the transfer body (18) is coated with a layer (20) of the flowable second material (8) and this layer (20) is brought into contact with the surface of the uppermost solidified material layer of the three-dimensional molded object (2) facing away from the base surface (4) in such a way that the flowable second material (8) is transferred from the transfer body (18) to the surface of the uppermost solidified material layer (14A) of the three-dimensional molded object (2) and forms a further material layer (21A, 21B, 21') on it, and wherein the further material layer (21A, 21B, 21') is solidified, characterized in that the flowable second material (8) is a material which has a higher viscosity than the flowable first material (6).wherein the surface area of ​​the transfer body (18) is coated with a layer (20) of the flowable second material (8) and this layer (20) is brought into contact with the surface of the uppermost solidified material layer of the three-dimensional molded object (2) facing away from the base surface (4) in such a way that the structure of the further material layer (21A, 21B, 21') transferred to this surface corresponds at least partially to that of the uppermost solidified material layer.

Description

[0001] The invention relates to a method for producing a three-dimensional shaped object by means of layer-by-layer material application, wherein geometric data for the shaped object, a carrier part with a base surface for receiving the three-dimensional shaped object, and a flowable first material and a different flowable second material are provided, wherein portions of the flowable first material are applied to the base surface and / or a solidified material layer of the three-dimensional shaped object located thereon, in accordance with the geometric data, in order to produce at least one material layer of the three-dimensional shaped object.and wherein the at least one material layer consisting of the flowable first material and at least one further material layer consisting of the flowable second material are solidified. The invention further relates to a device for producing a three-dimensional molded object by means of layer-by-layer material application, comprising a carrier part having a base surface for receiving the molded object, a first reservoir for receiving a flowable first material and a second reservoir for receiving a flowable second material that differs from the first flowable material, a dispensing device connected to the first reservoir for dispensing portions of the first material onto the base surface and / or a solidified material layer of the three-dimensional molded object located thereon, and a first positioning device.by means of which the carrier part and the dispensing device for applying the material portions to the base surface and / or the solidified material layer can be moved relative to one another, wherein the dispensing device and the first positioning device are connected to a control device which has a data memory for storing geometric data of the molded article to be produced, wherein the dispensing of the material portions and the positioning device can be controlled by means of the control device in dependence on the geometric data such that at least one material layer of the three-dimensional molded article consisting of the first material can be applied to the base surface and / or the solidified material layer of the three-dimensional molded article located thereon,and with at least one fixing device for solidifying at least one layer of material consisting of the flowable first material and for solidifying at least one further layer of material consisting of the flowable second material. A material portion is understood to mean, in particular, a droplet of material.

[0002] Such a device is known as Stratasys ® The Objet30 Pro is commercially available. The device has a holder to which a support element with an approximately rectangular base extending in a horizontal plane is attached. The three-dimensional object to be manufactured can be applied layer by layer to the base by depositing numerous superimposed layers of material.

[0003] Several printheads are arranged on the holder above the base surface. Each printhead has several nozzles arranged side by side in a row, from which portions of a flowable material can be dispensed onto the base surface or onto a solidified layer of the three-dimensional object located thereon. The rows of nozzles are arranged parallel to the two short edges of the rectangular base surface and can be moved parallel to the two long edges of the rectangular base surface by means of a positioning device. The positioning device also allows the support element containing the base surface to be moved towards and away from the printheads.

[0004] The nozzles of a first printhead are connected to a first reservoir filled with a low-viscosity first polymer. The nozzles of a second printhead are connected to a second reservoir filled with a low-viscosity second polymer, which differs from the first. The polymers can, for example, have different colors or different mechanical or chemical properties. However, in terms of strength after curing, they remain in the lower range, limited by the low viscosity of the materials. The printheads allow for the application of material layers consisting of the different polymers and / or a mixture of these polymers. For example, each printhead can dispense 50% of the material to be applied, so that the polymers from the first and second reservoirs mix in a 50:50 ratio during application.

[0005] Adjacent to the printheads is a fixing unit that incorporates an ultraviolet radiation source for crosslinking or solidifying the material layers applied by the printheads. The fixing unit, along with the printheads, is movable relative to the base surface.

[0006] The positioning devices and the printhead are connected to a control unit which controls the positioning devices and the material dispensing of the printhead in such a way that the molded object can be produced by layer-by-layer material application.

[0007] To produce a molded article, the print heads are positioned adjacent to a first edge of the substrate at a predetermined distance above it. Data for the geometry of a first material layer is loaded into a fast print buffer from a data memory containing geometric data for the molded article to be produced. The print heads are then continuously moved towards the opposite second edge of the substrate with the aid of the first positioning device. At the same time, by appropriately controlling the individual nozzles of the print heads, at least one portion of material is dispensed onto the substrate at those locations on the substrate where a first material layer of the molded article is to be formed. The individual nozzles are controlled depending on the current position of the print head in question and depending on the data in the print buffer.The flowable polymer material applied to the substrate is solidified by irradiation with ultraviolet radiation, which is generated using the fixing device.

[0008] When the printhead reaches the second edge of the substrate, its horizontal feed movement stops, and geometry data for an additional layer of material to be applied to the previously created layer is loaded from the data storage into the print buffer. Simultaneously, the support structure is lowered by an amount equal to the thickness of the previously created layer to allow for the application of another layer. The printheads are then continuously moved towards the first edge of the substrate by the positioning device. At the same time, by precisely controlling the nozzles at the points where the next layer is to be formed, at least one portion of material is dispensed onto the already completed and solidified layer.The flowable polymer material applied to the substrate is then solidified by irradiation with ultraviolet radiation, which is generated using the fixing device.

[0009] The above-mentioned process steps are repeated accordingly until the molded article is completed.

[0010] Since the nozzles used to apply the flowable material in the known device have small cross-sections to enable a correspondingly high resolution, the flowable materials must have a correspondingly low viscosity to be expelled from the nozzles. This viscosity is typically around 5 to 25 MPa·s. The polymer chains contained in the flowable materials must therefore be correspondingly short. However, this has the disadvantage that the molded objects produced layer by layer exhibit only comparatively low mechanical strength. Furthermore, the choice of printing materials has only limited influence on other properties of the molded objects produced layer by layer. Another disadvantage is that the layer-by-layer production of the molded objects is time-consuming.

[0011] Manufacturing processes and devices are known from the prior art that enable the application of material layers using transfer bodies: US 2002 / 0 119 584 A1 US 2015 / 0 024 169 A1 DE 20 52 038 A US 6 206 672 B1. Therefore, the object is to create a method and a device of the type mentioned above that enable the rapid production of a molded article. Furthermore, the method and a device should make it possible to adjust the physical and / or chemical properties within a wide range by appropriately selecting the flowable materials used to produce the material layers. In particular, the method and device should also be capable of producing molded articles that contain highly viscous polymers or polymers that cannot be digitally printed or applied.

[0012] According to the invention, this problem is solved with respect to the method of the type mentioned at the outset by the features of claim 1. These provide that a transfer body is provided, that a surface area of ​​the transfer body is coated with a layer of the flowable second material, and that this layer is brought into contact with the surface of the uppermost solidified material layer of the three-dimensional molded object facing away from the base surface in such a way that the flowable second material is transferred from the transfer body to the surface of the uppermost solidified material layer of the three-dimensional molded object and forms the further material layer on this surface, the structure of which corresponds at least partially to that of the uppermost solidified material layer of the three-dimensional molded object, and that the further material layer is solidified.

[0013] It is therefore a hybrid process in which the first material layer is "digitally" structured and solidified by applying portions of material to the areas where a first material layer of the molded article is to be. Then, at least one further material layer is applied to the first material layer using an "analog" contact printing process. In the contact printing process, a layer of the flowable second material is first created on the transfer body, and then material is transferred to the first material layer in those areas of this layer that correspond to the first material layer. Thus, the structure of the further material layer corresponds to that of the first material layer.Since contact printing allows even highly viscous materials to be applied to a structured material layer, it can also be used to produce molded objects containing polymers that are not digitally printable. This enables the molded object to achieve high mechanical strength.

[0014] In a preferred embodiment of the process, the material portions are sprayed onto the base surface and / or the solidified material layer of the three-dimensional molded object located thereon. This can be done, for example, using a nozzle.

[0015] In the case of an advantageous further development of the procedure, - that after the further material layer has solidified, portions of the flowable first material are applied to this material layer according to the geometric data in order to create a material layer of the three-dimensional shaped object, or- that after the further material layer has solidified, a surface region of the transfer body is coated with a layer of the flowable second material, and this layer is brought into contact with the surface of the uppermost solidified material layer facing away from the base surface, such that the flowable second material is transferred from the transfer body to the surface of the uppermost solidified material layer of the three-dimensional shaped object and forms a further material layer thereon, the structure of which corresponds to that of the uppermost solidified material layer, and that the uppermost material layer thus obtained is solidified. After the material layer produced by the contact printing process has solidified, at least one further material layer can be applied to it in the same way in order to reinforce the first-mentioned material layer.Alternatively, after the material layer produced using the contact printing process has solidified, at least one further material layer can be applied by applying portions of material to the material layer produced using the contact printing process.

[0016] In a further development of the process, a layer of the first material is applied to a solidified layer of the second material by applying portions of the first material in such a structured manner that at least one passage hole extending down to the underlying solidified layer is formed between two adjacent areas of the latter material layer in the plane of extension; the structured material layer is then solidified; the second material is then applied to this material layer by means of the transfer body; and at least one cross-sectional dimension of the passage hole is such that a) the pressure with which the second material is applied to the material layer containing the through-hole, and / or b) the thickness of the material with which the second material is applied to the material layer containing the through-hole, and / or c) is adapted to the viscosity of the second material, so that the through-hole is filled with the second material applied by means of the transfer body, and the second material comes into contact with the first-mentioned solidified material layer. The distance between the regions of the material layer located in the plane of extension of the material layer on both sides of the through-hole is preferably chosen to be smaller than the material thickness of this material layer, in particular less than half and preferably less than one-third of the material thickness. The through-hole can be open at the sides and, in particular, slit-shaped.

[0017] If the second material has a higher mechanical strength than the first material, the resulting molded object is reinforced both parallel to the material layers (e.g., horizontally) and perpendicular to them (e.g., vertically). It is even possible for the second material to form a honeycomb structure that reinforces the first material.

[0018] With regard to the device, the aforementioned problem is solved by the features of claim 3. These provide that the device has a transfer body and a coating device in contact with the second reservoir, by means of which at least a surface area of ​​the transfer body can be coated with a layer of the second material, and that the device has a second positioning device by means of which the surface area of ​​the transfer body can be brought into contact with the surface of the uppermost solidified material layer facing away from the base surface, such that the flowable second material, as a further material layer whose structure corresponds at least partially to that of the uppermost solidified material layer, is transferred from the transfer body to the surface of the uppermost solidified first material layer.

[0019] The invention thus provides a hybrid printing device which, in addition to the "digital" printing device with a dispensing unit for applying the material portions, has an "analog" contact printing device. This contact printing device has a transfer body onto which a layer of the flowable second material located in the second reservoir can be applied. The second material is then transferred to the previously produced, solidified first material layer, consisting of the first material, at those areas of this second layer that correspond to the first layer. The structure of the additional material layer applied to the first material layer in this way corresponds to the structure of the first material layer. Since highly viscous materials can also be applied to a structured material layer with the contact printing device, it is also possible to produce molded objects containing long-chain polymers with this device.This enables high mechanical strength of the molded part. Furthermore, the contact pressure device allows for the rapid production of the next material layer.

[0020] In a preferred embodiment of the invention, the dispensing device for dispensing the material portions has at least one digital material dispensing unit, preferably comprising a nozzle. A digital material dispensing unit is understood to be a device by means of which, depending on a logical signal, a predetermined quantity of the material to be printed is either dispensed or not.

[0021] In an advantageous embodiment of the invention, the dispensing device comprises at least one row of several material dispensing units arranged side by side for dispensing the material portions, and the row extends parallel to the base surface and transversely to the direction in which the dispensing device and the carrier part are movable relative to each other parallel to the base surface. It is even possible for the row of material dispensing units to extend across the entire width of the area to be printed. This enables rapid, even material application.

[0022] In a further development of the invention, the transfer body is designed as an application roller which can be rotated about a rotational axis arranged parallel to the base surface by means of the second positioning device. The application roller can, in particular, be a coating roller.

[0023] In a preferred embodiment of the invention, a feed roller is associated with the coating roller. The feed roller is rotatably driven about a roller axis arranged parallel to the rotational axis of the coating roller and, to coat its outer surface with the flowable second material, immerses a portion of its outer surface into the second reservoir. Furthermore, the outer surface of the feed roller is so closely adjacent to the outer surface of the coating roller that the second material applied to the outer surface of the feed roller can be transferred to the outer surface of the coating roller when the feed roller rotates about its axis. The feed roller enables simple and uniform coating of the outer surface of the coating roller with the flowable second material.

[0024] In a particularly preferred embodiment of the invention, the application roller is designed as a rotary screen printing roller. Due to the very high viscosity of the printing materials to be processed and the layer thickness, a particularly strong and rapid coating can be achieved.

[0025] In one embodiment of the invention, the arrangement formed by the dispensing device and the application roller, and the carrier part, are movable back and forth relative to each other along a straight line parallel to the base surface by means of the first positioning device. In this embodiment, the geometric data for the molded object are preferably provided in the Cartesian coordinate system, either in the form of pixels or in vectorized form. The coordinates of the locations where the material portions are dispensed onto the base surface or a solidified material layer of the three-dimensional molded object located thereon are also preferably given in the Cartesian coordinate system.

[0026] In another advantageous embodiment of the invention, the arrangement formed by the dispensing device and the application roller, and the carrier part, are rotatable relative to each other about an axis of rotation arranged normal to the base surface by means of the first positioning device, wherein the application roller is conical, and wherein the axis of rotation of the application roller passes through the axis of rotation. In this embodiment as well, the geometric data for the molded object are preferably provided in the Cartesian coordinate system, either in the form of pixels or in vectorized form. However, the coordinates of the locations where the material portions are dispensed onto the base surface or a solidified material layer of the three-dimensional molded object located thereon are preferably given in the polar coordinate system. The axis of rotation of the application roller can be a physical axis of rotation or an imaginary line.

[0027] It is advantageous if the assembly formed by the dispensing device and the application roller, and the support element, can be moved away from and towards each other perpendicular to the base surface by means of the first positioning device. The base surface can then be lowered by the thickness of each material layer after the application of that layer. This ensures that the distance between the dispensing device and the point where the material portions are applied remains constant for all material layers. The distance between the application roller and the point where the second material is applied also remains constant. Depending on the operating mode, the lowering can also be variable – for example, when different layer thicknesses are applied.

[0028] In a preferred embodiment of the invention, the second material, in its solidified state, exhibits greater mechanical strength than the first material and / or has different mechanical, electrical, or chemical properties than the first material. In this case, the material layers comprising the second material serve as reinforcing layers, which increase the mechanical strength or stability of the molded object or functionally enhance its properties. The reinforcement or enhancement can be adjusted by changing the layer thickness of the second material or the reinforcing material. The mechanical load-bearing capacity of the molded object increases with the layer thickness of the material layer(s) consisting of the second material. The material layers made of the lower-viscosity first material, which can be, for example, a standard polymer, serve as the build-up material.

[0029] The second material can be unfilled, preferably homogeneous. Alternatively, the second material can be filled, containing at least one organic filler and / or at least one inorganic filler. The filler can, for example, comprise particles, fibers, or platelets embedded in a carrier medium. The carrier medium can, for example, contain a solvent, a binder, and / or a reactive resin.

[0030] In an advantageous embodiment of the invention, the second material is electrically and / or optically and / or magnetically conductive, and the first material is electrically and / or optically and / or magnetically insulating. The device and method according to the invention are therefore also suitable for manufacturing printed electrical and / or optical circuits.

[0031] The method and device allow for a highly flexible and rapid implementation of electrical and / or optical connections in and on layer-by-layer printed three-dimensional objects. The printed material layer, dispensed by the material dispensing device, determines the path of the electrically and / or optically conductive traces applied to it. A key feature is the ability to print conductive traces inside the objects without requiring a separate printed circuit board.

[0032] Another special feature makes this solution cost-effective: the nano-inks with silver particles commonly available on the market are very expensive because they must be conductive yet low-viscosity. The conductive material usable for the invention can have a viscosity similar to that of the printing materials used in stencil printing, which are already widely available and more cost-effective than low-viscosity inks with nano-silver particles.

[0033] It should also be mentioned that the flowable materials can exhibit different barrier properties. For example, one of the materials may be permeable to gases and / or liquids, while the other is not.

[0034] To create overhangs, at least one support material for the first flowable material can be applied to the base surface and / or a solidified layer of the three-dimensional molded object using the dispensing device. After the support material has solidified and a layer of the second material has been applied to the support material using the transfer body and this layer has also solidified, the support material can be removed by contact with a solvent, such as water.

[0035] Exemplary embodiments of the invention are explained in more detail below with reference to the drawing. It shows: Fig. 1 a longitudinal section through a device for producing a three-dimensional shaped object during a first work pass in which two material layers of the shaped object are applied, wherein the device has a coating roller, Fig. 2 a longitudinal section through the in Fig. 1 Device shown during a first work pass in which two further layers of material are applied, Fig. 3 a longitudinal section through the in Fig. 1 Device shown during a work step in which a further layer of material, made of the same material as the first-mentioned layer of material, is applied to a layer of material of the molded object, Fig. 4 a longitudinal section through a device for producing a three-dimensional molded object, which has a rotary screen printing roller, Fig. 5 a longitudinal section through a printed circuit board, Fig. 6. A view of the printed circuit board and Fig. 7 a longitudinal section through a molded object,

[0036] One in Fig. 1. The device, designated as a whole by reference 1, for producing a three-dimensional shaped object 2 by means of layer-by-layer material application, has a plate-shaped support part 3 with a base surface 4 arranged in a horizontal plane for receiving the shaped object 2. The base surface 4 is essentially rectangular. However, other configurations are also conceivable, in which the base surface 4 can, in particular, have the shape of a circular disk or an annular disk.

[0037] The device further comprises a first reservoir 5 for receiving a flowable first material 6 and a second reservoir 7 for receiving a flowable second material 8 that differs from the flowable first material 6. As in Fig. As can be seen from Figure 1, the first reservoir 5 is designed as an essentially closed container and the second reservoir 7 as a tub.

[0038] The first reservoir 5 is connected via a line to a dispensing device 9 for the first material 6. The dispensing device 9 is designed as an inkjet printhead with a plurality of nozzles arranged in a row (not shown in detail in the drawing) that are directed to dispense portions 10 of the first material 6 onto the base surface 4 or onto a solidified layer of material of the three-dimensional molded object 2 located thereon. The row of nozzles is arranged parallel to the two short edges of the rectangular base surface 4 and extends across its entire width.

[0039] The support part 3 and the dispensing device 9 can be moved relative to each other in and against the direction of arrow 11 by means of a first positioning device which is not shown in detail in the drawing.

[0040] The dispensing device 9 and the first positioning device are connected to a control device 12, which has a data memory 13 for storing geometric data of the molded article 2 to be produced. The control device 12 can be used to control the dispensing of the material portions 10 and the positioning device in a manner known per se depending on the geometric data, such that material layers 14A of the three-dimensional molded article 2 consisting of the flowable first material 6 can be applied as a layer stack to the base surface 4 and / or the solidified material layer of the three-dimensional molded article 2 located thereon.

[0041] To smooth the uppermost material layer 14A consisting of the flowable first material 6, a smoothing roller 15 rotatable about its (imaginary) axis of rotation is arranged in front of the dispensing device 9 in the direction of arrow 11. The axis of rotation of the smoothing roller 15 is arranged parallel to the base surface 4 and normal to the direction of arrow 11. Furthermore, the imaginary axis of rotation of the smoothing roller 15 is fixed in relation to the dispensing device 9, i.e. the dispensing device 9 and the smoothing roller 15 on the one hand, and the carrier part 3 on the other, can be displaced relative to one another in and against the direction of arrow 11 by means of the first positioning device.

[0042] A gap is formed between the smoothing roller 15 and the base surface 4, or rather the surface plane of the uppermost, hardened material layer located thereon. The vertical dimension of this gap corresponds to the thickness of the material layer to be applied. The gap extends over the entire width of the base surface 4 to be coated.

[0043] To solidify the material layers 14A, which consist of the flowable first material 6, a first fixing device 16 is arranged in the direction of arrow 11 upstream of the smoothing roller 15. This device has a UV radiation source (not shown in detail in the drawing) by means of which UV radiation 17 can be emitted onto the uppermost material layer 14A. The wavelength and intensity of the UV radiation 17 are selected such that polymers and / or copolymers located in the uppermost material layer 14A crosslink.

[0044] In the direction of arrow 11 in front of the first fixing device 16, the device 1 has a transfer body 18 designed as a flexographic printing roller and a coating device 19 in contact with the second reservoir, by means of which at least a surface area of ​​the transfer body 18 can be coated with a layer 20 of the second material 8.

[0045] The surface area of ​​the transfer body 18 can be brought into contact with the surface of the uppermost solidified material layer facing away from the base surface by means of a second positioning device not shown in detail in the drawing, such that the flowable second material 8 is transferred from the transfer body 18 to the surface of the uppermost solidified first material layer 14A as a further material layer 21A, the structure of which corresponds to that of the uppermost solidified material layer 14A.With the aid of the second positioning device, the cylindrical transfer body 18 can be rotated about an imaginary axis of rotation, which is arranged parallel to the base surface 4 and normal to the direction of the arrow 11, such that the layer 20 of the second material 8 located on the lateral surface of the transfer body 18 rolls onto the uppermost solidified material layer when the carrier part 3 and the dispensing device 9 are moved relative to each other in the direction of the arrow 11.

[0046] The first and second positioning devices are preferably driven independently of each other by means of separate drive motors. However, it is also conceivable that the first and second positioning devices share a common drive motor.

[0047] In the Fig. In the embodiment shown in Figures 1 to 3, the coating device has a feed roller 22 which is rotatably driven about a roller axis arranged parallel to the axis of rotation of the transfer body 18. To coat its outer surface with the flowable second material 8, the feed roller 22 dips with a lower portion of its outer surface into the second reservoir 7 or the flowable second material 8 contained therein.

[0048] The outer surface of the feed roller 22 is so closely adjacent to the outer surface of the transfer body 18 that the second material 8 applied to the outer surface of the feed roller 22 can be transferred to the outer surface of the transfer body 18 during a rotational movement of the feed roller 22 about its roller axis.

[0049] To solidify the uppermost layer 21A, consisting of the flowable second material 8, a second fixing device 23 is arranged in the direction of arrow 11 in front of the transfer body 18. This device has a UV radiation source (not shown in detail in the drawing) by means of which UV radiation 24 can be emitted onto the uppermost layer 21A. The wavelength and intensity of the UV radiation 24 are selected such that polymers and / or copolymers located in the uppermost layer 21A crosslink. The fixing devices 16 and 23 are fixed in position relative to the dispensing device 9.

[0050] In summary, it follows that with the aid of the device 1, a structured material layer 14A consisting of the first material 6 is first produced and solidified by means of a digital printing process 25 and that then a further material layer 21A consisting of the second material 8 with a corresponding structure is applied and solidified onto this material layer 14A by means of an analog printing process 26.

[0051] After the first material layer 14A, consisting of the first material 6, and the first further material layer 21A, consisting of the second material 8, have been completed on the base surface 4 as described above, the carrier part 3 is lowered by the first positioning device 4 by the sum of the wall thicknesses of these material layers 14A and 21A relative to the dispensing device 9, the smoothing roller 15, the fixing devices 16 and 23, and the transfer body 18. Furthermore, the carrier part 3 is moved back to its starting position in the opposite direction to arrow 11, in order to then apply a second material layer 14B, consisting of the first material 6, and a second further material layer 21B, consisting of the second material 8, to the solidified first further material layer 21A in the same manner. Fig. 2) These steps are repeated until the molded object 2 is completed.

[0052] In Fig. Figure 3 shows that with the help of the transfer body 18, several further material layers 21A, 21B consisting of the second material 8 can also be stacked directly on top of each other to increase the material thickness. Although these layers consist of the same material, they are in Fig. For the sake of readability, layer 21A is shown differently in black and layer 21B in white. During the application of the second additional material layer 21B, the dispensing device 9 and the first fixing device 16 are inactive.

[0053] In the Fig. In the embodiment shown in Figure 4, the transfer body 18 is designed as a rotary screen printing roller. This roller has a perforated, sieve-like outer surface. The second reservoir 7 is arranged in the inner cavity of the rotary screen printing roller.

[0054] The dimensions of the perforation holes provided in the outer surface are adapted to the viscosity of the second material 8 such that the second material 8 can be pressed through the perforation holes by means of a squeegee 27 that rests linearly on the inner surface of the cylinder wall of the rotary screen printing roller. Outside the effective range of the squeegee 27, the second material 8 does not pass through the perforation holes.

[0055] Furthermore, the in Fig. 4 device shown in the Fig. 1 to 3 device shown, so that the description of Fig. 1 to 3 for Fig. 4 applies accordingly.

[0056] The device can also be used to manufacture printed electrical circuit boards 28 ( Fig. 5 and Fig. 6) In this process, an insulating body 29 with a structured surface is first produced and solidified by layer application of an electrically insulating material using the dispensing device 9. In a further process step, at least one further layer 21' of a highly viscous, electrically conductive material is applied and solidified onto the uppermost structured material layer 14' using the transfer body 18.

[0057] In the Fig. In the embodiment shown in Figure 5, the material layer 14' comprising the first material 6 is structured such that it has at least one through-hole 30 which penetrates the material layer 14' transversely to its plane of extension down to the material layer below. The cross-sectional dimension or the clear width of the through-hole 30 is so small that the material film of the second material 8 does not tear at the edge of the through-hole 30 when the material layer 21' is applied. As a result, the second material 8, which serves as a reinforcing material, flows into the through-hole 30 when the material layer 21' is applied. The material layer 21' thus forms a support structure that reinforces the printed circuit board 28 both parallel to its plane of extension (horizontally) and transversely to it (vertically).This measure reduces the risk, particularly in the case of bending stress on the circuit board 28, of the material layer 21' serving as a conductor track detaching from the insulation body 29.

[0058] Fig. Figure 7 shows a longitudinal section through a molded article 2, in which the second material of the material layers 21A, 21B serving as a reinforcement layer extends through through-holes 30 of the respective underlying layer 14A, 14B consisting of the first material 6. It is clearly visible that material layer 21B contacts the underlying material layer 21A through the through-holes 30. The reinforcement structure formed in this way reinforces the molded article 2 both parallel to the material layers 14A, 14B, 21A, 21B and transversely thereto.

[0059] The clear width of the passage holes 30 is less than 25% of the vertical distance between the material layers 14A, 14B consisting of the first material 6. This prevents the material film of the second material 8 from tearing at the edge of the passage holes 30 when the material layers 21A, 21B are applied.

[0060] As in Fig. As can be further seen in Figure 7, a passage opening 31 formed in material layer 14B, whose clear width is larger than the vertical distance between material layers 14A and 14B, is not filled with the second material 8. In the area of ​​this passage opening 31, the structure of material layer 21B therefore corresponds to that of the underlying material layer 14B.

Claims

[1] A method for producing a three-dimensional shaped article (2) by layer-by-layer material application, wherein geometric data for the shaped article (2), a carrier part (3) with a base surface (4) for receiving the three-dimensional shaped article (2) and a first and a different flowable second material (6, 8) are provided, wherein material portions (10) of the flowable first material (6) are applied according to the geometric data to the base surface (4) and / or a solidified material layer of the three-dimensional shaped article (2) located thereon using at least one nozzle in order to produce at least one material layer (14A, 14B, 14') of the three-dimensional shaped article (2), wherein the at least one material layer (14A, 14B, 14') consisting of the flowable first material (6) is solidified, wherein a transfer body (18) is provided,a surface area of ​​the transfer body (18) is coated with a layer (20) of the flowable second material (8) and this layer (20) is brought into contact with the surface of the uppermost solidified material layer of the three-dimensional shaped article (2) facing away from the base surface (4) in such a way that the flowable second material (8) is transferred from the transfer body (18) to the surface of the uppermost solidified material layer (14A) of the three-dimensional shaped article (2) and forms a further material layer (21A, 21B, 21') thereon, and wherein the further material layer (21A, 21B, 21') is solidified, , characterized bythat a material is provided as the flowable second material (8) which has a higher viscosity than the flowable first material (6), wherein the surface region of the transfer body (18) is coated with a layer (20) of the flowable second material (8) and this layer (20) is brought into contact with the surface of the uppermost solidified material layer of the three-dimensional shaped article (2) facing away from the base surface (4) in such a way that the structure of the further material layer (21A, 21B, 21') transferred onto this surface corresponds at least in regions to that of the uppermost solidified material layer. [2] Method according to claim 1, characterized bythat a material layer (14B) made of the first material (6) is applied in a structured manner to a solidified material layer (21A) consisting of the second material (8) by applying material portions (10) in such a way that between two regions of this material layer (14B) that are adjacent to one another in the plane of extension of the last-mentioned material layer (14B), at least one through-hole (30) extending to the underlying solidified material layer (21A) is formed, that the material layer (14B) structured in such a way is then solidified, that thereafter the second material (8) is applied to this material layer (14B) by means of the transfer body (18), and that at least one cross-sectional dimension of the through-hole (30) is such a) the pressure with which the second material (8) is applied to the material layer (14B) having the through-hole (30), and / or b) the material thickness with which the second material (8) is applied to the material layer (14B) having the through-hole (30), and / or c) is adapted to the viscosity of the second material (8), that the through-hole (30) is filled with the second material (8) applied by means of the transfer body (18) and the second material (8) comes into contact with the first-mentioned solidified material layer (21A). [3] Device (1) for producing a three-dimensional shaped object (2) by layer-by-layer material application, comprising a carrier part (3) having a base surface (4) for receiving the shaped object (2), a first reservoir (5) for receiving a first material (6) and a second reservoir (7) for receiving a second material (8) different from the first material (6), at least one dispensing device (9) connected to the first reservoir (5) for dispensing material portions (10) of the first material (6) onto the base surface (4) and / or a solidified material layer of the three-dimensional shaped object (2) located thereon, a first positioning device by means of which the carrier part (3) and the dispensing device (9) for applying the material portions (10) to the base surface (4) and / or the solidified material layer can be moved relative to one another in a positioning direction,wherein the dispensing device (9) and the first positioning device are connected to a control device (12) having a data memory (13) for storing geometric data of the molded article to be produced, wherein the dispensing of the material portions (10) and the positioning device can be controlled by means of the control device (12) in dependence on the geometric data such that at least one material layer (21A, 21B, 21') of the three-dimensional molded article (2) consisting of the first material (6) can be applied to the base surface (4) and / or the solidified material layer of the three-dimensional molded article (2) located thereon, wherein the device (1) has a transfer body (18) and a coating device (19) in contact with the second reservoir (7), by means of which at least one surface region of the transfer body (18) can be coated with a layer (20) of the second material (8),and wherein the device (1) has a second positioning device, by means of which the layer (20) of the second material (8) located on the surface region can be brought into contact with the surface of the uppermost solidified material layer facing away from the base surface (4) in such a way that the second material (8) is transferred as a further material layer (21A, 21B, 21') from the transfer body (18) to the surface of the uppermost solidified first material layer, , characterized bythat the first reservoir (5) is designed to hold a flowable first material (6) and the second reservoir (7) is designed to hold a flowable second material (8), that the coating device (19) is designed to coat the surface region of the transfer body (18) with a layer (20) of the second material (8) which can be brought into contact with the surface of the uppermost solidified material layer facing away from the base surface (4) in such a way that the structure of the further material layer (21A, 21B, 21') corresponds at least in regions to that of the uppermost solidified material layer (14A), and that the device (1) has at least one fixing device (16, 23) for solidifying the at least one material layer (14A, 14B, 14') consisting of the flowable first material (6) and for solidifying at least one further material layer (21A, 21B,21') and wherein the dispensing device (9) for dispensing the material portions (10) has at least one digital material dispensing unit having a nozzle, [4] Device (1) according to claim 3, characterized by that the dispensing device (9) has at least one row with a plurality of material dispensing units arranged next to one another for dispensing the material portions, and that the row extends parallel to the base surface (4) and transversely to the direction in which the dispensing device (9) and the carrier part (3) are movable relative to one another parallel to the base surface (4). [5] Device (1) according to one of claims 3 to 4, characterized by that the transfer body (18) is designed as an application roller which can be driven in rotation about a rotation axis arranged parallel to the base surface (4) with the aid of the second positioning device. [6] Device (1) according to claim 5, characterized bythat the application roller is designed as a rotary screen printing roller. [7] Device (1) according to one of claims 5 or 6, characterized by that the arrangement formed from the dispensing device (9) and the application roller and the carrier part (3) can be moved back and forth relative to one another by means of the first positioning device along a straight line arranged parallel to the base surface. [8] Device (1) according to one of claims 5 to 7, characterized by that the arrangement formed from the dispensing device (9) and the application roller and the carrier part (3) can be rotated relative to one another by means of the first positioning device about an axis of rotation arranged normal to the base surface (4), that the application roller is conical, and that the axis of rotation of the application roller runs through the axis of rotation. [9] Device (1) according to one of claims 5 to 8, characterized bythat the arrangement formed from the dispensing device (9) and the application roller and the carrier part (3) can be moved away from and towards each other by means of the first positioning device normal to the base surface (4). [10] Device (1) according to one of claims 3 to 9, characterized by that the second material (8) in the solidified state has a greater mechanical strength than the first material (6) and / or that the second material (8) has different mechanical, electrical or chemical properties than the first material (6). [11] Device (1) according to one of claims 3 to 10, characterized by that the second material (8) is electrically and / or optically and / or magnetically conductive and the first material (6) is electrically and / or optically and / or magnetically insulating.

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