Device and method for producing a component, in particular a dental restoration, in layers

Abstract

A device (10) for producing a component (12), in particular a dental restoration (14), in layers is described. At least one component layer of the component (12) comprises both a first material (M1) and a second material (M2). Alternatively, at least one component layer is produced from the first material (M1) and a further component layer adjacent thereto is produced from the second material (M2). The device (10) comprises a build space (20) which is delimited by a build platform (24), which can be driven to move, and a curing unit (28), wherein the curing unit (28) is designed to cure first material (M1) and / or second material (M2) present in the build space (20). Furthermore, the device (10) comprises a first container (30) for first material (M1), a first conveying unit (34) for conveying first material (M1) into the build space (20), a second container (44) for second material (M2), and a second conveying unit (48) for conveying second material (M2) into the build space (20). The first conveying unit (34) and the second conveying unit (48) are at least temporarily inversely motion-coupled, wherein the motion coupling is mechanical and / or control technology-related. Furthermore, methods for producing a component (12) in layers is presented.

Description

[0001] IVOCLAR VIVADENT AG Munich, 10. Dezember 2025 Our reference: I1409WO / SE

[0002] IVOCLAR VIVADENT AG

[0003] Bendererstrasse 2, 9494 Schaan, Liechtenstein

[0004] Device and method for producing a component, in particular a dental restoration, in layers

[0005] The invention relates to a device for producing a component, in particular a dental restoration, in layers.

[0006] The invention is also directed to methods for producing a component, in particular a dental restoration, in layers.

[0007] Such methods and devices for producing components in layers are known in their own right. In the course of such methods, the component to be produced is constructed layer by layer on a substrate or on a build platform. The substrate or the build platform can often be moved incrementally, wherein one increment corresponds to a layer thickness or layer height of the component layer to be produced. The substrate or build platform can frequently be moved in a vertical direction which is sometimes referred to as the Z-direction. Therefore, an increment can also be referred to as Z-resolution or vertical resolution. In this regard, this is also referred to as additive or generative manufacture. Some of these methods are also referred to as 3D printing. Dental technology is an area of application for such methods. In particular, replacement teeth or partial or full prostheses comprising same can be produced in layers. The same applies to parts of replacement teeth. Generally speaking, dental restorations can be produced in layers. The aim is always for the dental restoration to look as true to the original as possible, i.e. to differ as little as possible in appearance from natural teeth and / or natural gums.

[0008] Therefore, the object of the present invention is to further improve the fidelity of dental restorations produced in layers, i.e. to permit the production of dental restorations having a natural-looking appearance. In other words, it should become possible to produce dental restorations which approximate natural teeth or natural gums as closely as possible.

[0009] The object is achieved by a device for producing a component, in particular a dental restoration, in layers. At least one component layer of the component comprises both a first material and a second material. Alternatively, at least one component layer is produced from the first material and a further component layer adjacent thereto is produced from the second material. The device comprises a build space which is delimited by a build platform, which can be driven to move, and a curing unit opposite the build platform, wherein the curing unit is designed to cure first material and / or second material present in the build space. Furthermore, the device comprises a first container for first material, which is connected to the build space in a materialconducting manner. The device also comprises a first conveying unit for conveying first material from the first container into the build space. Moreover, the device comprises a second container for second material, which is connected to the build space in a material-conducting manner. Furthermore, the device comprises a second conveying unit for conveying second material from the second container into the build space. The first conveying unit and the second conveying unit are at least temporarily inversely motion-coupled. The motion coupling is mechanical and / or control technology-related.

[0010] Therefore, the device in accordance with the invention is, on the one hand, suitable and designed for producing a component, in particular a dental restoration, in layers, wherein at least one component layer of the component comprises both a first material and a second material. It includes two alternatives. According to a first alternative, the first material and the second material are mixed within the component layer. According to a second alternative, the component layer comprises both the first material and the second material, but the first material and the second material are unmixed. On the other hand, the device in accordance with the invention is suitable and designed for producing a component, in particular a dental restoration, in layers, wherein the component comprises mutually adjacent component layers consisting of different materials, i.e. wherein at least one component layer consisting of first material is adjacent to a further component layer consisting of second material. In the device in accordance with the invention, a component to be produced can be constructed layer by layer on the build platform. For this purpose, a first material is conveyed from the first container into the build space by means of the first conveying unit. Alternatively or in addition, a second material is conveyed from the second container into the build space by means of the second conveying unit. The curing unit is used to cure a component layer consisting of first material and / or second material in the build space. By reason of the fact that the build platform can be driven to move, the build platform can be displaced by one increment after a component layer has been produced so that the subsequent component layer can be produced. The increment is e.g. 50 to 100 micrometres. The above-described suitability of the device for producing component layers which comprise both the first material and the second material, as well as for producing mutually adjacent component layers from different materials, is determined by the fact that the first conveying unit and the second conveying unit are at least temporarily inversely motion- coupled. This means that, at least temporarily, a conveying direction of the first conveying unit and a conveying direction of the second conveying unit are oriented in opposite directions. This includes a first alternative, in which the conveying direction of the first conveying unit is oriented towards the build space, i.e. first material is conveyed towards the build space, and the conveying direction of the second conveying unit is oriented in a direction pointing away from the build space, i.e. second material is conveyed out of the build space or at least conveyance of the second material out of the build space is enabled. This also includes a second alternative, in which the conveying direction of the first conveying unit is oriented in a direction away from the build space and the conveying direction of the second conveying unit is oriented in the direction of the build space. The motion coupling of the first conveying unit and the second conveying unit ensures that first material is conveyed into the build space and second material is conveyed out of the build space in a specified ratio. The same applies if second material is conveyed into the build space and first material is conveyed out of the build space. For example, the motion coupling ensures that a volume increment of first or second material conveyed into the build space corresponds to a volume increment of the respective other of first and second material conveyed out of the build space. In this manner, the material to be processed into a component layer can be exchanged in the build space. That is to say that first material present in the build space can be replaced by second material and vice versa. It is understood that for this purpose the first material and the second material must be present in the uncured state. Furthermore, the at least temporary inverse motion coupling ensures that both first material and second material can be present in the build space, i.e. in a component layer which is to be produced. The first material and the second material can be mixed. However, it is alternatively also feasible for the first material and the second material to be present next to one another without being mixed. Thus, dental restorations which are true to the original can be produced by means of the device in accordance with the invention. This relates in particular to three ways of producing dental restorations which are true to the original. On the one hand, the trueness to the original can be increased by mixing the first material and the second material. Furthermore, by arranging first material and second material next to one another in the same component layer without mixing, the dental restoration can be produced according to the so-called core-shell principle, wherein a core region of the dental restoration which simulates the dentine of a real tooth, is produced from a different material than a shell region which surrounds the core region at least in sections and simulates an enamel of a real tooth. Furthermore, a dental restoration which is true to the original can also be produced by arranging component layers consisting of different materials or differently coloured materials next to one another.

[0011] It is noted that in the case of the device in accordance with the invention, the fact that the build platform can be driven to move also means in particular that the build platform can be held in a motionless manner. In other words, the build platform can be locked or fixed. This is particularly advantageous in situations where the first material in the build space is to be replaced by second material or vice versa. Specifically, if the build platform does not move, one of first material and second material can be removed from the build space with a particularly high degree of efficiency and the respective other of first material and second material can be introduced into the build space. The same applies to situations, in which a mixture of first material and second material which is located in the build space is to be changed. With regard to the present invention, the first material and the second material are different. This means that the first material and the second material differ from one another at least with regard to one material property. Equally, it is possible for the first material and the second material to differ from one another at least with regard to a plurality of material properties. Examples of material properties include colour, discolouration stability, translucency, opacity, opalescence, gloss stability, colour brightness, fluorescence, wear resistance, degree of abrasion, hardness, fracture resistance, as well as further clinically relevant parameters and / or material behaviour of the materials in the uncured, i.e. not yet polymerised, state, such as rheological behaviour, e.g. viscosity, or parameters influencing the rheological behaviour, such as degree of filling, etc. These material properties relate in particular to polymerised, i.e. cured, (partial) regions of the first material and / or the second material. Consequently, the trueness to the original of the dental restoration can be further increased by skilful selection of first material and second material, in particular by skilful selection of those material properties, with regard to which the first material and the second material may differ from one another.

[0012] Furthermore, with regard to the present invention the first material and the second material must be flowable. In particular, the first material and the second material are liquids, wherein a viscosity of the first material and a viscosity of the second material can each extend over a wide viscosity range. Thus, the viscosity of the first material and the viscosity of the second material can be substantially the same, similar or different.

[0013] In one variant, a viscosity of the first material and a viscosity of the second material can be in the range of liquid water, i.e. in the range of 1.0 mPa*s to 100 mPa*s, assuming a temperature of 23°C.

[0014] Typically, the viscosity is determined at 23°C, i.e. at room temperature, using a plate-plate viscometer (shear rate 10 / s).

[0015] The viscosity range can be characterised e.g. by an interval of + / -10% or + / -5%. In another variant, the first material and the second material can be paste-like, i.e. have, at a temperature of 23°C, a significantly higher viscosity than liquid water. Optionally, it is feasible to heat up the first material and / or the second material in order to lower the viscosity.

[0016] Materials for stereolithographic processing are preferably adjusted such that their viscosity, depending upon the material temperature during the processing process, is in the range of 100 mPa*s to 100 Pa*s, preferably 250 mPa*s to 50 Pa*s, particularly preferably 500 mPa*s to 49 Pa*s. The material temperature during the processing process is preferably in the range of 10°C to 70°C, particularly preferably 20°C to 65°C or 30°C to 60°C.

[0017] In a preferred example, a viscosity of the first material and a viscosity of the second material are similar. In this regard, a viscosity of the first material can differ by + / -10% or less from the viscosity of the second material or vice versa. Alternatively, as already mentioned, it is also possible to select the viscosity of the first material and the viscosity of the second material differently, i.e. to process a low-viscosity material and a high-viscosity material. The viscosities can differ from one another by several factors. In this regard, materials with different viscosities can be obtained by providing different filler contents and / or formulation properties.

[0018] In general, it can be stated that the rheological properties of the materials to be processed are always adapted to the desired application.

[0019] The device in accordance with the invention is designed in particular to carry out a stereolithography method. In this case, the curing unit comprises an exposure unit which in turn comprises e.g. a laser. Other examples of exposure units have an LCD (liquid crystal display) or a projector, in particular a so-called digital light projector and so precise, in particular pixel - by-pixel, exposure is possible. Consequently, first material and / or second material can be cured by means of the curing unit by exposing the first material and / or the second material, which are present in the build space, to light, in particular by means of so-called photopolymerisation. For this purpose, the build space can have a transparent wall portion, e.g. in the form of an exposure window. In one example, an inner side of the build space is coated with silicone, polytetrafluoroethylene (PTFE) and / or polydimethylsiloxane (PDMS).

[0020] It is understood that even though the device in accordance with the invention has been explained on the basis of its suitability for producing at least one component layer which comprises both a first material and a second material, it is also possible to produce components, in particular dental restorations comprising a plurality of such component layers by means of the device in accordance with the invention. In particular, the device in accordance with the invention can be used to produce components, of which the majority of component layers comprise both a first material and a second material. The same applies to the production of components by means of the device in accordance with the invention, wherein at least one component layer is produced from the first material and at least one further component layer adjacent thereto is produced from the second material. This means that the device in accordance with the invention can also be used to produce components comprising a plurality of such pairs of mutually adjacent component layers which are produced from different materials.

[0021] According to an example, the first container and the second container are fluidically coupled via the build space. In other words, the build space is arranged between the first container and the second container when taking a fluidic perspective. As has been mentioned before, the first container for first material is connected to the build space in a material-conducting manner. Moreover, the second container for second material is connected to the build space in a materialconducting manner. If the first container and the second container are fluidically coupled via the build space, the first container and the second container are connected in a materialconducting manner via the build space. This means that first material provided in the first container can be conveyed into or through the build space and into or towards the second container, e.g. by operating the first conveying unit. In the same manner, second material provided in the second container can be conveyed into or through the build space and into or towards the first container, e.g. by operating the second conveying unit. This enhances the flexibility of using the first material and / or the second material when producing a component, in particular a dental restoration, in layers. In this context, at least one component layer of the component comprises both the first material and the second material, wherein the first material and the second material can be mixed or unmixed. Alternatively, at least one component layer is produced from the first material and a further component layer adjacent thereto is produced from the second material. Furthermore, the configuration in which the first container and the second container are fluidically coupled via the build space facilitates hydromechanical motioncoupling of the first conveying unit and the second conveying unit via the first material and / or via the second material as will be explained in more detail further below.

[0022] Furthermore, the device can comprise a mixing contour for mixing the first material and / or the second material, wherein the mixing contour is arranged within the build space or adjacent to the build space. Alternatively, the mixing contour can also be referred to as a mixing link or mixing structure. This includes three alternatives. According to a first alternative, the mixing contour is configured for mixing the first material. This means that the first material can be intrinsically mixed by means of the mixing contour. The first material can be homogenised in this manner. According to a second alternative, the mixing contour is configured for mixing the second material. This means that the second material can be intrinsically mixed by means of the mixing contour. The second material can be homogenised in this manner. According to a third alternative, the mixing contour is configured for mixing the first material with the second material. In this alternative, the mixing contour effects reliable and uniform mixing of the first material and the second material. The mixing always requires flowability of the materials. The mixing contour locally increases the flow rate of the material. This creates different flow rates within the material which ultimately cause the mixing. The provision of the first material in homogenised form, the second material in homogenised form or the mixture of first and second material in homogenised form leads to homogeneous component layers and thus to a dental restoration which is true to the original.

[0023] It is also possible for the device to comprise a separating element for keeping first material and second material separated. Such a separating element is used in particular if a mixture of first material and second material is undesired, i.e. if each portion of the component to be produced is to be produced from only one of first material and second material. In this regard, the separating element can be provided in the form of a slide or a separating bar which is arranged between the first material and the second material, so that the first material and the second material do not have a common boundary layer. The separating element can preferably be moved. Therefore, the separating element can be moved within the build space and optionally can also be moved into and out of the build space. In order to move the separating element into the build space, it may be necessary to move the build platform to a suitable position so that a collision between the separating element and already produced component portions can be excluded. Overall, the separating element can be used to keep the first material and the second material reliably separated. This reliably prevents undesired mixtures of first material and second material. As a result, dental restorations of a high quality can be produced.

[0024] In one example, the separating element is movably mounted between the first material and the second material. The separating element can be driven by means of first material and / or second material. This means that the separating element can be moved indirectly by conveying first material into the build space by means of the first conveying unit. Alternatively, the separating element can be moved indirectly by conveying the second material into the build space by means of the second conveying unit. In this manner, the separating element can be moved simply and reliably.

[0025] According to one embodiment, the first container is formed by an inner space of a cylinder. In addition, the first conveying unit comprises a piston which is received at least in sections in the inner space of the cylinder and can be displaced in the inner space. Alternatively or in addition, the second container is formed by an inner space of a cylinder. In addition, the second conveying unit comprises a piston which is received at least in sections in the inner space of the cylinder and can be displaced in the inner space. In such a configuration, the container which is designed as a cylinder and an allocated piston can also be referred to as a cartridge. In particular, the term “cartridge” also includes material contained therein. Such a structure of the containers and conveying units is structurally simple. Furthermore, such a combination of container and conveying unit means that the allocated material can be conveyed with high precision and reliability.

[0026] The motion coupling can be hydromechanical via the first material and / or via the second material. Alternatively, the first conveying unit and the second conveying unit can be mechanically coupled. According to a further alternative, the first conveying unit and the second conveying unit can be mechanically separate from one another and can be coupled in terms of control technology. As already mentioned previously, the motion coupling must be inverse. The conveying directions of the first conveying unit and the second conveying unit are thus oriented in opposite directions. In the first alternative, this is effected by virtue of the fact that the first conveying unit and the second conveying unit are coupled hydromechanically, or more precisely hydrostatically, via the first material and the second material. This is particularly easy to understand if both the first conveying unit and the second conveying unit are designed as pistons, as already explained. If a space between the piston forming the first conveying unit and the piston forming the second conveying unit is filled with first material and second material substantially free of air, movement of one of the pistons in the direction of the build space causes the respective other piston to move away from the build space by reason of the hydromechanical coupling. During the hydromechanical motion coupling, it is therefore sufficient to actively move one of the conveying units and to enable the respective other conveying unit for passive movement. A coupling of the first conveying unit and the second conveying unit outside the first material and / or the second material is not necessary for the hydromechanical motion coupling. Therefore, a device which uses a hydromechanical motion coupling can be constructed in a structurally simple manner. In the second alternative, the first conveying unit and the second conveying unit are mechanically coupled. This coupling is effected outside the first material and the second material. This means that, in this alternative, the first conveying unit and the second conveying unit are inversely motion-coupled by means of mechanical components, such as push rods, gear wheels, etc. In this way, a reliable motion coupling of the first conveying unit and the second conveying unit can be achieved. In the third alternative, the first conveying unit and the second conveying unit are mechanically separate from one another. However, the first conveying unit and the second conveying unit are mechanically coupled in terms of control technology. This implies that each of the first conveying unit and the second conveying unit is allocated an actuator which can be controlled or regulated. The control technology-related motion coupling now makes provision that a movement of the first conveying unit or the second conveying unit thus leads to an inverse movement of the respective other of the first conveying unit and the second conveying unit because the movement of the first conveying unit or the second conveying unit leads to a control technology-related signal being communicated to the respective other conveying unit, which causes the respective other conveying unit to perform an inverse movement. This type of inverse motion coupling is also comparatively simple and reliable. All three alternatives of the inverse motion coupling ensure that first material and second material can be exchanged precisely and reliably in the build space or mixed in the build space. Therefore, it is possible to produce dental restorations which are true to the original.

[0027] Furthermore, in a further example the first conveying unit or the second conveying unit are hydromechanically motion-coupled to the build platform at least temporarily via the first material and / or the second material. Therefore, the build platform can be moved indirectly by means of the first conveying unit or the second conveying unit, i.e. via the first material and / or the second material, e.g. by one increment corresponding to a thickness of a component layer to be produced, e.g. 50 to 100 micrometres. More generally speaking, the thickness of the component layer is limited merely by the opacity and reactivity of the material.

[0028] According to one variant, the build platform, the first conveying unit and the second conveying unit can be selectively and individually locked in order to motion-couple in each case two of the build platform, the first conveying unit and the second conveying unit hydromechanically via the first material and / or via the second material. In one example in which the build platform is to be moved by means of the first conveying unit, the second conveying unit can thus be selectively and individually locked, i.e. fixed. As a result, the build platform and the first conveying unit are reliably and precisely motion-coupled. This means that, by reason of the coupling via the first material and / or the second material, a movement of the first conveying unit leads to a movement of the build platform. In one example in which the build platform is to be moved by means of the second conveying unit, the first conveying unit can be selectively and individually locked, i.e. fixed. As a result, the build platform and the second conveying unit are reliably and precisely motion-coupled. This means that, by reason of the coupling via the first material and / or the second material, a movement of the second conveying unit leads to a movement of the build platform. In one example in which the second conveying unit is to be moved by means of the first conveying unit, the build platform can be selectively and individually locked, i.e. fixed. As a result, the first conveying unit and the second conveying unit are reliably and precisely motion-coupled. This means that, by reason of the coupling via the first material and / or the second material, a movement of the first conveying unit leads to a movement of the second conveying unit. In one example in which the first conveying unit is to be moved by means of the second conveying unit, the build platform can be selectively and individually locked, i.e. fixed. As a result, the second conveying unit and the first conveying unit are reliably and precisely motion-coupled. This means that, by reason of the coupling via the first material and / or the second material, a movement of the second conveying unit leads to a movement of the first conveying unit. The selective and individual locking, i.e. fixing, of the build platform, the first conveying unit or the second conveying unit leads to precise and reliable motion coupling. This in turn has the effect that the first material in the build space can be easily and reliably replaced by second material or vice versa. Likewise, the first material and the second material can be reliably mixed. This is achieved in particular without the build platform being moved.

[0029] The build platform can be designed as an end surface of a piston guided in a cylinder. Such a structure of the build platform is structurally simple. Furthermore, such a configuration ensures that the build platform can be moved by means of a hydromechanical coupling via the first material and / or the second material by means of the first conveying unit and / or by means of the second conveying unit. In one example, the device further comprises a third container for a third material, which is connected to the build space in a material-conducting manner, and a third conveying unit for conveying the third material from the third container into the build space. The first conveying unit, the second conveying unit and the third conveying unit are inversely motion-coupled in pairs at least temporarily. The motion coupling is mechanical or control technology-related. In particular, the motion coupling is hydromechanical and is effected via the first material, the second material and / or the third material. Consequently, a third material can be used in order to produce the component, in particular the dental restoration. Furthermore, the first material or the second material in the build space can be replaced by third material. The same applies vice versa. This also makes it possible to use mixtures of the third material and the first material and / or second material in order to produce the component. This further increases the trueness of the dental restoration to the original.

[0030] It is understood that the present invention is not restricted to the use of three containers and three materials. Of course, it is also possible to use four or more containers and materials. The explanations given in connection with the first and second containers thus also apply accordingly to devices having three, four or more containers.

[0031] In one variant, the device further comprises an excess container for receiving excess first material and / or excess second material. The excess container is connected to the build space in a material-conducting manner. This means that, during production of the component, excess first material and / or excess second material can be conveyed into the excess container. This increases the quality of the component layers, so that overall increased trueness to the original of the dental restoration is achieved. In particular, the excess first material and / or the excess second material can be conveyed into the excess container by means of the first conveying unit and / or the second conveying unit by means of hydromechanical coupling. It is understood that in a case where at least one further material, i.e. a material in addition to the first material and the second material, is used, the excess container can also be designed to receive excess further material. The same applies if several further materials are used. In addition, the object is achieved by a method for producing a component, in particular a dental restoration, in layers. At least one component layer comprises both a first material and a second material. The method comprises:

[0032] - providing a layer of uncured first material and curing at least a portion of the layer so that the layer comprises a region of cured first material and a region of uncured first material,

[0033] - replacing the uncured first material in the layer with uncured second material so that the layer comprises a region of cured first material and a region of uncured second material, and

[0034] - curing at least a portion of the layer which comprises a second material so that the layer comprises a region of cured first material, a region of cured second material, and a region of uncured second material.

[0035] The layers provided in this regard are delimited e.g. by a build platform or already produced component layers and a curing unit. By means of this method, a component, in particular a dental restoration, can thus be produced in layers, wherein at least one component layer comprises both a first material and a second material. The first material and the second material are present next to one another within the component layer. Therefore, the first material and the second material are not mixed. In this manner, in particular a component, preferably a dental restoration, can be produced according to the core-shell principle, wherein a core region of the dental restoration is produced from a different material than a shell region which surrounds the core region at least in sections. Therefore, it is possible to produce dental restorations which are true to the original.

[0036] Preferably, when carrying out the method in accordance with the invention, the particular region in which the layer of first material and second material is produced, i.e. the particular region in which the component to be produced is created, is hermetically sealed from a surrounding area. This means that this region is tightly sealed from a surrounding area, in particular in relation to the first material and the second material. In particular, this also applies to the step in which uncured first material is replaced by uncured second material. Therefore, it is possible to produce a qualitatively high-grade component.

[0037] This method in accordance with the invention is performed preferably by means of a device in accordance with the invention.

[0038] As already mentioned, it is understood that even though the method in accordance with the invention has been explained merely using one component layer which comprises both a first material and a second material, it is also possible to produce components, in particular dental restorations, comprising a plurality of such component layers by means of the method in accordance with the invention. In particular, the method in accordance with the invention can be performed to produce components, of which the majority of component layers comprise both a first material and a second material. Likewise, it is possible to produce components and / or component layers which comprise more than two materials.

[0039] As already explained in connection with the device in accordance with the invention, the curing can be effected by exposure to light. In particular, the method in accordance with the invention can be combined with a stereolithography method which is known per se.

[0040] According to one embodiment, the uncured first material in the layer can be replaced by uncured second material by displacement of the uncured first material by means of uncured second material. This means that in a situation where uncured first material is present in the build space, i.e. in the layer, this uncured first material is replaced by uncured second material by virtue of the fact that uncured second material is urged or pushed into the build space, i.e. into the layer. As a result, the uncured first material is displaced, i.e. is conveyed out of the build space. In this manner, the first material can be easily and reliably replaced by the second material.

[0041] The method can further comprise production of a flow geometry for first material by means of local curing of second material. Alternatively or in addition, the method can comprise production of a flow geometry for second material by means of local curing of first material. Further alternatively or in addition, the method can comprise uncured first material and / or uncured second material flowing around a flow geometry. In the alternative last referred to, the flow geometry is thus utilised in connection with the present method, but is not produced in the course of the method. In all variants, the flow geometries have the effect that a desired flow profile can be set for the first material and / or the second material, e.g. a locally increased flow rate. It is understood that, particularly in the first two alternatives, the flow geometry for first material and / or the flow geometry for second material can be a part of the component to be produced, but generally is not a part of the component to be produced. Therefore, the flow geometry for first material and / or the flow geometry for second material is produced merely in order to influence material flows. Either the flow geometry for first material and / or the flow geometry for second material is separate from the component to be produced or must be separated from the component to be produced in a post-processing step. In this regard, the flow geometry can include predetermined breaking points, e.g. in the form of a perforation. Such a predetermined breaking point makes it easier to separate the flow geometry from the component to be produced. The flow geometry for first material serves to influence a flow of first material in such a manner that the first material is guided precisely and reliably into the particular region of the layer in which it is to be provided. In particular, it is possible in this manner for a flow rate of the first material to be increased in a targeted manner when replacing material. The same applies to the flow geometry for second material. Overall, by utilising the flow geometry, the first material and / or the second material can be precisely and reliably arranged within the layer and so a dental restoration which is true to the original can be produced.

[0042] According to one variant, the flow geometry for first material delimits a region, in which first material is to be cured, at least in sections, and / or comprises a flow channel for first material. Alternatively or in addition, the flow geometry for second material delimits a region, in which second material is to be cured, at least in sections, and / or comprises a flow channel for second material. This makes it possible to precisely define the particular regions of the layer in which the first material and / or the second material is to be arranged. It is understood that a flow channel for first material must be connected in a material-conducting manner to the first container which contains first material. In the same manner, it is understood that a flow channel for second material must be connected in a material-conducting manner to the second container which contains second material.

[0043] In one example, the flow channel has a substantially constant cross-section. This means that the largest cross-section of the flow channel and the smallest cross-section of the flow channel differ by a maximum of 30%. Preferably, this difference is 20% or less. More preferably, this difference is 10% or less. This produces a reliable flow within the flow channel.

[0044] In this regard, the flow geometry for first material can be designed in such a way that the first material must flow around an already cured portion of the component, which is to be produced, on an outer side at a comparatively high flow rate. A relatively large part of the build space can be occupied by cured material.

[0045] According to another example, a cross-section of the flow channel changes, i.e. the crosssection is substantially not constant. A largest cross-section of the flow channel and a smallest cross-section of the flow channel differ considerably, e.g. by 50% to 100%, e.g. 90%. In this manner, the flow within the flow channel can also be influenced in a targeted manner.

[0046] It is understood that the flow geometry for first material and / or the flow geometry for second material must always be adapted to the specific application, i.e. to the component which is to be specifically produced. Furthermore, the material properties of the first material and / or the second material must be taken into account. For example, cross-section sizes must be adapted to the respective viscosity because cross-sections which are too small lead to comparatively high flow resistances. Cross-sections which are too large lead to a comparatively low flow rate. This can lead to inadequate replacement of uncured first material with uncured second material or vice versa. It is understood that the cross-sections are delimited by a layer thickness. Furthermore, the strength of the cured material must be taken into account because this determines which compressive forces which are produced by flow resistances can be withstood by the cured material. Furthermore, a flow rate of the uncured material and a resulting shear rate must be taken into account in this regard. It must also be taken into account that cured material can cause the build platform, which can be driven to move, to adhere to fixed portions of the build space. In simple terms, the cured material acts as an adhesive. Under certain circumstances, such adhesion effects can lead to undesired damage to the component to be produced and must therefore be influenced in a targeted manner.

[0047] In one example, the flow geometry comprises so-called support structures, i.e. structures which support the component to be produced during the production process.

[0048] Another example includes the closing off of flow channels produced by means of flow geometries. This has the advantage that no more material can flow through the flow channel during the further course of the method. This increases the efficiency of the method.

[0049] In yet another example, the method comprises a cleaning step. The flow geometries are used in order to guide a cleaning agent, e.g. a cleaning agent containing isopropanol or a cleaning agent containing water. The cleaning step serves to remove uncured material which has remained adhered to the component in an undesired manner during production of the component. The use of the flow geometries for the cleaning step can improve an efficiency of the cleaning step. In addition, cleaning can thus be performed comparatively quickly. It is likewise possible to save on cleaning agents.

[0050] The method can also comprise removing excess uncured first material and / or excess uncured second material. As already mentioned, the quality of the component produced can be increased thereby. In the case of a dental restoration, trueness to the original can be further increased in this manner.

[0051] In a case in which the particular device used for carrying out the method in accordance with the invention comprises a excess container, it is of course also feasible to produce a flow geometry which influences a flow in the direction of the excess container. The object is also achieved by a method for producing a component, in particular a dental restoration, in layers. At least one component layer comprises both a first material and a second material. The method comprises:

[0052] - providing uncured first material and uncured second material within a layer,

[0053] - mixing the uncured first material and the uncured second material within the layer, and

[0054] - curing at least a portion of the mixture of uncured first material and uncured second material within the layer.

[0055] The layers provided in this regard are delimited e.g. by a build platform or an already produced layer of the component and a curing unit. This method can thus be used for producing a component in layers, in which a mixture of first material and second material is present in at least one layer. Therefore, it is possible to produce dental restorations which are true to the original.

[0056] This method in accordance with the invention is performed preferably by means of a device in accordance with the invention.

[0057] It is understood that even though the method in accordance with the invention has been explained with reference to a single pairing of a first component layer, which is produced form the first material, and of an adjacent second component layer which is produced from the second material, it is also possible by means of the method in accordance with the invention to produce components which comprise a plurality of such pairs of mutually adjacent component layers which are produced from different materials.

[0058] The uncured first material and the uncured second material can be mixed by moving a contact surface present between the uncured first material and the uncured second material within the layer. In other words, the first material and the second material are moved within the layer in order to produce a mixture of first material and second material. In this way, the first material and the second material can be mixed in a reliable manner. The invention will be explained hereinafter with the aid of various exemplified embodiments which are illustrated in the attached drawings. In the figures:

[0059] Fig. 1 shows a perspective sectional view of a device in accordance with the invention, wherein a component in the form of a dental restoration, which is produced in layers, is provided in the interior of the device,

[0060] Fig. 2 shows the device of Fig. 1 in a side view,

[0061] Figs. 3 to 7 show steps of a method in accordance with the invention which is carried out by means of the device of Figs. 1 and 2,

[0062] Fig. 8 shows a method variant in which, in addition to the component, a flow geometry is produced in layers from cured building material,

[0063] Fig. 9 shows another method variant in which, in addition to the component, a flow geometry is produced in layers,

[0064] Fig. 10 shows a variant of the device of Figs. 1 and 2 which comprises blocking slides,

[0065] Figs. 11 and 12 show another variant of the device of Figs. 1 and 2 which comprises a separating element,

[0066] Figs. 13 and 14 show an additional variant of the device which comprises a mixing contour,

[0067] Fig. 15 shows a further variant of the device which comprises a mixing contour, and

[0068] Fig. 16 shows a device in accordance with the invention according to another exemplified embodiment. Fig. 1 shows a device 10 for producing a component 12 in layers. In the illustrated embodiment, the component 12 is a dental restoration 14.

[0069] Although the component 12, in the present case the dental restoration 14, does not belong with the device 10, it is illustrated in Fig. 1 for ease of explanation of the device 10.

[0070] Specifically, the dental restoration 14 in Fig. l is a replacement tooth produced according to the core-shell principle. This means that the dental restoration 14 comprises a core region 16, which is to be produced from a first material Ml, and a shell region 18, which at least partially surrounds the core region 16 and is to be produced from a second material M2.

[0071] The first material Ml and the second material M2 differ from one another with regard to at least one material property.

[0072] The device 10 comprises a build space 20 in which the component 12, i.e. the dental restoration 14, is produced in layers. In the illustrated embodiment, the build space 20 is formed as the end of a cylinder 22 having a substantially circular cross-section. On a first axial side, the build space 20 is delimited by a build platform 24 which can be driven to move and on which the component 12 to be produced can be constructed in layers.

[0073] In the illustrated embodiment, the build platform 24 is designed as the axial end surface of a piston 26 which is guided in the cylinder 22. The piston 26 can thus be displaced along a cylinder axis A.

[0074] On a side opposite the build platform 24, the build space 20 is delimited by a curing unit 28, which is designed to cure first material Ml and / or second material M2 present in the build space 20. For this purpose, the curing unit 28 comprises a transparent wall element 29 which delimits the build space 20 in the region of the curing unit 28.

[0075] In the illustrated embodiment, the device 10 is designed to perform a stereolithography method. Accordingly, the curing unit 28 is designed to expose the first material Ml and / or the second material M2 to light for curing purposes. It is understood that for this purpose, the first material Ml and the second material M2 must be tailored to suit the curing unit 28 in such a way that they can be cured by exposure to light by means of the curing unit 28.

[0076] The device 10 also comprises a first container 30 for first material Ml. In the illustrated embodiment, first material Ml is stored in the container 30.

[0077] The first container 30 is connected to the build space 20 in a material-conducting manner via a first channel 32.

[0078] Furthermore, the device comprises a first conveying unit 34 which is designed to convey the first material from the container 30 into the build space 20.

[0079] In the illustrated embodiment, the first container 30 is formed as a portion of a cylinder 36 having a substantially rectangular cross-section.

[0080] The first conveying unit 34 comprises a piston 38 which is received in sections in the inner space of the cylinder 36 and is displaceable along a cylinder axis B of the cylinder 36.

[0081] Furthermore, the first conveying unit 34 comprises an actuator 40 which is illustrated merely schematically in Figs. 1 and 2 and by means of which the piston 38 can optionally be displaced along the cylinder axis B.

[0082] The actuator 40 is designed such that it can actively move the piston 38 in the direction of the build space 20 when the actuator 40 is activated. Furthermore, the actuator 40 is designed such that the piston 38 can be passively displaced in a deactivated state of the actuator 40.

[0083] Furthermore, the device 10 has a first blocking unit 42, by means of which the piston 38 can be locked. This means that a movement of the piston 38 can be blocked by means of the first blocking unit 42. The first blocking unit 42 is also illustrated merely schematically in Figs. 1 and 2. The device 10 also comprises a second container 44 for second material M2. In the illustrated embodiment, second material M2 is stored in the container 44.

[0084] The second container 44 is connected to the build space 20 in a material-conducting manner via a second channel 46.

[0085] Furthermore, the device comprises a second conveying unit 48 which is designed to convey second material M2 from the container 44 into the build space 20.

[0086] In the illustrated embodiment, the second container 44 is formed as a portion of a cylinder 50 having a substantially rectangular base surface.

[0087] The second conveying unit 48 comprises a piston 52 which is received in sections in the inner space of the cylinder 50 and is displaceable along a cylinder axis C of the cylinder 50.

[0088] In the illustrated embodiment, the cylinder axes B and C coincide.

[0089] Furthermore, the second conveying unit 48 comprises an actuator 54 which is illustrated merely schematically in Figs. 1 and 2 and by means of which the piston 52 can optionally be displaced along the cylinder axis C.

[0090] The actuator 54 is designed such that it can actively move the piston 52 in the direction of the build space 20 when the actuator 54 is activated. Furthermore, the actuator 54 is designed such that the piston 52 can be passively displaced in a deactivated state of the actuator 54.

[0091] Furthermore, the device 10 has a second blocking unit 56, by means of which the piston 52 can be locked. This means that a movement of the piston 52 can be blocked by means of the second blocking unit 56. The second blocking unit 56 is also illustrated merely schematically in Fig. 1.

[0092] As already explained, the build platform 24 and thus the piston 26, on which the build platform 24 is formed, can be driven to move. For this purpose, an optional actuator 58, illustrated merely schematically in Figs. 1 and 2, is coupled to the piston 26 so that the piston 26 can be moved optionally along the cylinder axis C by means of the actuator 58.

[0093] The actuator 58 is designed such that it can actively move the piston 52 in the direction away from the build space 20 when the actuator 58 is activated. Furthermore, the actuator 58 is designed such that the piston 52 can be passively displaced in a deactivated state of the actuator 58.

[0094] Furthermore, the device 10 has a third blocking unit 60, by means of which the piston 26 can be locked. This means that a movement of the piston 26 can be blocked by means of the third blocking unit 60. The third blocking unit 60 is also illustrated merely schematically in Fig. 1.

[0095] By reason of the fact that first material Ml and / or second material M2 is present in the build space 20, in the first container 30 and in the second container 44, it is possible to hydromechanically couple in each case two of the first conveying unit 34, second conveying unit 48 and build platform 24 at least temporarily via the first material Ml and / or the second material M2. It is understood that in this case it is further assumed that first material Ml is also present in the first channel 32 and second material M2 is present in the second channel 46.

[0096] Such a hydromechanical coupling is inverse. This means that the hydromechanically coupled elements, i.e. two elements selected from the first conveying unit 34, second conveying unit 48 and build platform 24 move with the opposite sign.

[0097] A hydromechanical coupling requires the two hydromechanically coupled elements, i.e. two elements selected from the first conveying unit 34, second conveying unit 48 and build platform 24 can be moved in principle. That is to say that the respectively associated blocking units 42, 56, 60 enable such a movement. This is explained hereinafter with reference to a method for producing a component, in particular a dental restoration 14, in layers, wherein the method is carried out by means of the device 10.

[0098] By means of the method, a component 12 is produced in layers, wherein at least one component layer comprises both a first material Ml and a second material M2, but the first material Ml and the second material M2 are not mixed. In other words, a component 12 can be produced according to the core-shell principle.

[0099] The steps of this method are explained hereinafter with reference to Figs. 3 to 7. For ease of explanation, the production of the component 12 as a whole is not explained hereinafter, but instead merely the production of a layer of the component 12 which comprises both the first material Ml and the second material M2.

[0100] An initial situation is shown in Fig. 3. In this initial situation, a layer of uncured first material Ml is provided below the already produced, i.e. already cured layers of the component 12.

[0101] In the present case, the core region 16 of the component 12 is produced from the first material Ml.

[0102] Accordingly, a portion of the layer of uncured first material Ml is cured by means of the curing unit 28. Only the portion of the layer of uncured first material Ml which corresponds to the further progression of the core region 16 to be produced is cured. All other portions of the layer of uncured first material Ml remain uncured.

[0103] In Fig. 3, the particular region of the layer consisting of uncured first material Ml which is cured is denoted by a rectangle Hl.

[0104] As a result, i.e. after curing, the layer thus comprises both cured first material Ml and uncured first material Ml.

[0105] Then, the uncured first material Ml in the layer is replaced by uncured second material M2. For this purpose, the uncured first material Ml is displaced by uncured second material M2.

[0106] For this purpose, on the one hand the third blocking unit 60 is used to lock the particular piston 26, on which the build platform 24 is provided.

[0107] The first conveying unit 34 and / or the second conveying unit 48 are basically movable. This means that the piston 38 can basically move relative to the cylinder 36 and the piston 52 can basically move relative to the cylinder 50.

[0108] In the present case, the actuator 54 is used to displace the uncured first material Ml. By means of this actuator 54, the piston 52 is moved in the direction of the build space 20, so that the second material M2 is urged starting from the second container 44 through the second channel 46 into the build space 20.

[0109] This is illustrated in Fig. 4 by arrows.

[0110] As a result, the uncured first material Ml is displaced from the build space 20. Since the piston 38 is movable within the cylinder 36, this first material can be urged back into the container 30, wherein the piston 38 is displaced within the cylinder 36 in a direction away from the build space 20.

[0111] The cured portions of the first material Ml in the build space 20 are no longer flowable and therefore remain in place.

[0112] In this situation, the first conveying unit 34 and the second conveying unit 48 are thus hydromechanically inversely motion-coupled via the first material Ml and the second material M2.

[0113] After this step, the layer comprises a region of cured first material Ml and a region of uncured second material M2. Subsequently, at least one portion of the layer comprising second material M2 is cured. Again, the curing unit 28 is used for this purpose.

[0114] This is illustrated in Fig. 5 in which the cured region of second material M2 is denoted by two rectangles H2.

[0115] Consequently, the layer comprises a region of cured first material Ml, a region of cured second material M2 and a region of uncured second material M2.

[0116] Therefore, the layer of the component 12 to be produced is complete. The build platform 24 must now be raised by one increment in order to produce the next layer of the component 12.

[0117] In the illustrated embodiment, one such increment is 50 to 100 micrometres.

[0118] Therefore, in the present case the portions of the next layer comprising first material Ml are initially produced.

[0119] Therefore, the second conveying unit 48 is locked by means of the second blocking unit 56. That is to say that the piston 52 can no longer move relative to the cylinder 50.

[0120] The build platform 24 and the first conveying unit 34 are basically movable.

[0121] The actuator 40 of the first conveying unit 34 is used to displace the build platform 24, whereby a new, uncured layer is made available.

[0122] This actuator 40 is used to push the piston 38 of the first conveying unit 34 in the direction of the build space 20.

[0123] Since the piston 26 is movable within the cylinder 22, the build platform 24 can thereby be moved by one increment, wherein the movement is oriented away from the curing unit 28.

[0124] In this step, the first conveying unit 34 and the build platform 24 are thus hydromechanically inversely motion-coupled via the first material Ml and the second material M2. In simple terms, first material Ml can be pushed under the last cured layer of the component 12 by reason of the locking, i.e. fixing, of the piston 52.

[0125] This is illustrated in Fig. 6 by arrows.

[0126] As soon as the build platform has been displaced by one increment, it is locked by the third blocking unit 60.

[0127] However, since the region of the previously produced layer still has uncured second material M2 which, however, is not to be used for producing the core region 16, in a subsequent step the second material M2 is displaced by means of the first material Ml.

[0128] For this purpose, the piston 26 remains locked by means of the third blocking unit 60.

[0129] The first conveying unit 34 and / or the second conveying unit 48 are basically movable.

[0130] The actuator 40 of the first conveying unit 34 is now used. This actuator 40 is used to push the piston 38 in the direction of the build space 20. Second material M2 is displaced by means of the first material Ml and is pushed back into the container 44. This is possible because the piston 52 of the second conveying unit 48 can move back.

[0131] This is illustrated in Fig. 7 by arrows.

[0132] The first material Ml can now be cured, at least in sections, by means of the curing unit 28, as explained initially with reference to Fig. 3.

[0133] In the illustrated example, the device 10 thus comprises a total of three pistons 26, 38, 52. During the production of the component 12, it is possible for two of these pistons 26, 38, 52 to be inversely hydromechanically coupled in a selective and temporary manner. The respective third one of these pistons 26, 38, 52 is locked, i.e. it cannot move. In this way, it is possible to move only one piston at a time by means of an allocated actuator 40, 54, 58. The respective other one of the pistons is also moved by reason of the hydromechanical coupling without it having to be driven separately.

[0134] In another example, such a hydromechanical coupling is not used. Instead, two of the three pistons 26, 38, 52 can each be mechanically coupled in a selective and temporary manner. The mechanical coupling is established via components which are not illustrated in greater detail and which extend outside the cylinders 22, 36, 50. For example, these components comprise a linkage.

[0135] The above-described method for producing a component 12 in layers can also be carried out with a device 10 in which a mechanical coupling is used instead of the hydromechanical coupling.

[0136] In a further example, both a hydromechanical coupling and a mechanical coupling, which extends outside the cylinders 22, 36, 50, are omitted. Instead, a control technology-related coupling is used.

[0137] In this example, it is imperative that each of the pistons 26, 38, 52 is coupled to an actuator. These actuators are coupled in terms of control technology such that they can be actuated in a coordinated manner. In this way, an inverse motion coupling can be established between the first conveying unit 34 and the second conveying unit 48 as well as between one of the first conveying unit 34 and the second conveying unit 48 and the build platform 24. In this example, the blocking units can thus be omitted.

[0138] As a consequence, the method explained above can also be carried out with a device 10 which is constructed according to this example.

[0139] Fig. 8 illustrates a variant of the method explained above. Only those aspects which go beyond the already explained basic method are explained hereinafter. In the method variant of Fig. 8, in addition to the component 12 to be produced, a cylindrical component 62 which surrounds the component 12 is also produced.

[0140] However, the cylindrical component 62 is not used as a dental restoration. On the contrary, the cylindrical component 62 serves to prevent undesired mixing of the first material Ml and the second material M2.

[0141] This is achieved by virtue of the fact that regions in which mixing of the first and the second material potentially takes place are cured by means of the curing unit 28 and so the cylindrical component 62 is formed. As a consequence, the first material Ml and the second material M2 are no longer flowable in these regions. Therefore, these materials can no longer be mixed with the respective other material.

[0142] Fig. 9 shows a further method variant. As previously, only those aspects which go beyond the already explained basic method are discussed.

[0143] In the variant shown in Fig. 9, in addition to the component 12 to be produced, a flow geometry 64 is also produced.

[0144] In the example shown in Fig. 9, this flow geometry 64 is manufactured from first material Ml, i.e. by local curing of first material Ml. This means that in the particular step in which the first material Ml is cured by means of the curing unit 28 in order to produce a layer of the core region 16, those portions of the flow geometry 64 which are associated with the relevant layer are also cured.

[0145] As a consequence, less material Ml has to be pushed back into the first container 30 than in the basic method during the production of those portions of the component layer from the second material M2 compared to the basic method.

[0146] This means that less second material M2 is also required because the amount of second material M2 required is merely that needed to fill the portions of the layer, which are left free by the flow geometry 64, with second material M2. Therefore, the flow geometry 64 delimits a region, in which second material is to be cured, at least in sections, and / or comprises a flow channel for second material M2.

[0147] Furthermore, by reason of the fact that a portion of the build space 20 is taken up by the flow geometry 64, a cross-section for a flow of the second material M2 is reduced and thus a flow rate is increased. In this way, uncured first material can be reliably replaced with uncured second material. In simple terms, the first material is flushed away more reliably by reason of the increased flow rate.

[0148] In this way, flow around the core region 16 with the second material M2 can be configured in a particularly reliable manner, so that the shell region 18 can be produced with a particularly high degree of reliability and precision.

[0149] It is understood that, of course, it is also possible in the same way to produce a flow geometry 64 from second material which is configured to influence a flow consisting of first material Ml.

[0150] Alternatively, it is also possible to provide the flow geometry 64 in a fixed manner, i.e. as a component of the device 10.

[0151] A further variant of the method and a variant of the device 10 are illustrated in Fig. 10.

[0152] As before, only the differences compared to the already explained basic method and the differences compared to the previously explained aspects of the device 10 are mentioned.

[0153] In the variant of Fig. 10, the device 10 comprises a separating element 66 for keeping first material Ml and second material M2 separated. More precisely, the separating element 66 comprises a first blocking slide 68, by means of which the first channel 32 can be selectively blocked and selectively unblocked, and comprises a second blocking slide 70, by means of which the second channel 46 can be selectively blocked and selectively unblocked. Proceeding from the basic method, the method for producing the component 12 is thus changed in such a manner that in those process steps in which first material Ml is urged from the first container 30 through the first channel 32 into the build space 20, the second blocking slide 70 is closed. Therefore, no material can flow back into the second container 44.

[0154] In this regard, it is particularly advantageous if the device 10 is additionally equipped with an optional excess container 72 for receiving excess first material Ml and / or excess second material M2, wherein the excess container 72 is connected in a material-conducting manner to the build space 20. If this is the case, the particular material which is present in an uncured state in the build space 20 can be displaced into the excess container 72 by means of the first material Ml.

[0155] In the same way, in those method steps in which second material M2 is urged from the second container 44 through the second channel 46 into the build space 20, the first blocking slide 68 is closed. Therefore, no material can flow back into the first container 30.

[0156] In this regard, it is again particularly advantageous if the device 10 is additionally equipped with an excess container 72 for receiving excess first material Ml and / or excess second material M2, wherein the excess container 72 is connected in a material-conducting manner to the build space 20. If this is the case, the particular material which is present in an uncured state in the build space 20 can be displaced into the excess container 72 by means of the second material M2.

[0157] In other words, the method comprises removing excess uncured first material Ml and / or excess uncured second material M2.

[0158] In Fig. 10, the excess container 72 is shown only as a dashed line and indicated schematically.

[0159] Figs. 11 and 12 show a further variant of the device 10 in which a separating element 66 is likewise used. In contrast to the variant shown in Fig. 10, however, this separating element 66 is now designed as a displaceable stopper 74, which can optionally close the first channel 32 or the second channel 46. For this purpose, the stopper 74, i.e. the separating element 66, can be pushed through the build space 20. For this purpose, the stopper 74 can be coupled to an actuator, not illustrated in greater detail. For example, the stopper 74 and the allocated actuator are magnetically coupled. Alternatively, no such actuator can be provided and the stopper 74 can be moved only by means of the first material Ml and the second material M2.

[0160] When carrying out the method, the device 10 in Figs. 11 and 12 functions in substantially the same way as the device 10 in Fig. 10. It must only be borne in mind that, by reason of the geometric expansion of the stopper 74, the build platform 24 must always be raised if the stopper 74 is to be displaced from the first channel 32 through the build space 20 into the second channel 46 or vice versa.

[0161] It is understood that in the device 10 of Figs. 11 and 12, the stopper 74 must be displaced once from the first channel 32 to the second channel 46 during the production of each layer.

[0162] A further variant of the device 10 is illustrated in Figs. 13 and 14, wherein Fig. 14 shows a sectional view along the plane XIV-XIV in Fig. 13. Again, only the differences with respect to the variants already explained will be discussed.

[0163] In this variant, the device comprises a mixing contour 88 which in the present case comprises a plurality of protrusions arranged within the first channel 32, and comprises a plurality of protrusions arranged within the second channel 46. In other words, the mixing contour 88 is arranged adjacent to the build space 20. Thus, if the first material Ml flows through the first channel 32 into the build space 20, the first material Ml must flow around those protrusions of the mixing contour 88 which are arranged in the first channel 32. As a result, the first material Ml is thoroughly mixed. In the same way, the second material M2 must flow around those protrusions of the mixing contour 88 which are arranged in the second channel 46 if the second material Ml flows through the second channel 46 into the build space 20. As a result, the second material M2 is thoroughly mixed.

[0164] In the variant shown in Figs. 13 and 14, the mixing contour 88 is produced from first material Ml or second material M2. The curing unit 28 must therefore be appropriately dimensioned and designed so that it can cure protrusions associated with the mixing contour 88 in the first channel 32 and in the second channel 46. Accordingly, the walls of the first channel 32 and the second channel 46 must also be transparent in those regions in which the mixing contour 88 is to be arranged, so that the first material Ml and the second material M2 can be cured to produce the mixing contour 88.

[0165] An alternative method for producing a component 12, in particular the dental restoration 14, in layers can also be carried out by means of the device 10 according to Figs. 13 and 14. A component layer can be produced which comprises both the first material Ml and the second material M2, wherein the first material Ml and the second material M2 are mixed.

[0166] According to this method, uncured first material Ml and uncured second material M2 must be provided within the layer.

[0167] Likewise, the first material Ml and the second material M2 within the layer can be mixed. For this purpose, a contact surface present between the uncured first material Ml and the uncured second material M2 is moved within the layer. This is effected by moving the first conveying unit 34 and the second conveying unit 48. The piston 26 which supports the build platform 24 is locked by means of the third blocking unit 60.

[0168] The first conveying unit 34 and the second conveying unit 48 are, as already explained, hydromechanically inversely motion-coupled. Therefore, in order to mix the first material Ml and the second material M2, the piston 38 and the piston 52 are periodically moved in a reciprocating manner along the respective piston axes B, C. This is effected at an amplitude which allows parts of the second material M2 to be urged into the first channel 32 by means of the piston 52 and parts of the first material Ml to be urged into the second channel 46 by means of the piston 38.

[0169] In other words, the contact surface between the first material Ml and the second material M2 is periodically moved in a reciprocating manner between the first channel 32 and the second channel 46. By interacting with the protrusions of the mixing contour 88, the first material Ml and the second material M2 are mixed in this manner.

[0170] Subsequently, at least a portion of the mixture of uncured first material Ml and uncured second material M2 is cured within the layer by means of the curing unit 28.

[0171] In contrast to the first method already explained, both the first material Ml and the second material M2 are now present in the same layer, wherein, however, the first material Ml and the second material M2 are mixed together.

[0172] Fig. 15 shows a further variant of the device 10. Again, a mixing contour 88 is provided. However, in contrast to the variant shown in Figs. 13 and 14, the mixing contour is now not produced from first material Ml and / or second material M2, but is designed as a fixed part of the first flow channel 32 and the second flow channel 46. In this variant, the curing unit 28 therefore does not have to be designed to cure first material Ml and / or second material M2 within the first channel 32 and / or within the second channel 46.

[0173] In all the aforementioned variants in which a mixing contour 88 is provided, the mixing contour is composed of a plurality of cuboid mixing elements, of which the edges are angular, i.e. as sharp-edged as possible. This sharp-edged design results in high flow rate differences in the region of the edges, which ensure reliable mixing.

[0174] Fig. 16 shows a further variant of the device 10. Again, only the differences with respect to the device 10 already explained will be discussed. The device shown in Fig. 16 comprises a total of five containers and five conveying units. This means that in total five materials can be processed by means of the device 10 of Fig. 16. Furthermore, the device 10 of Fig. 16 comprises an excess container 72.

[0175] In this regard, all five containers and the respective associated conveying units are constructed in exactly the same way as explained in the preceding embodiments for the first container 30, the first conveying unit 34, the second container 44 and the second conveying unit 48.

[0176] Accordingly, with regard to the first container 30, the first conveying unit 34, the second container 44 and the second conveying unit 48, reference can be made to the above explanations.

[0177] Furthermore, the device 10 of Fig. 16 comprises a third container 90 for third material, wherein the third container 90 is connected in a material-conducting manner to the build space 20 in the same way as the first container 30 and the second container 44 via a third channel.

[0178] Furthermore, the device comprises a third conveying unit 92 which is designed to convey third material from the third container 90 into the build space 20.

[0179] In the illustrated embodiment, the third container 90 is formed as a portion of a cylinder 94 having a substantially rectangular base surface. It is understood that the rectangular base surface is merely exemplary and that other shapes of base surface are also possible, e.g. round.

[0180] The third conveying unit 92 comprises a piston 96 which is received in sections in the inner space of the cylinder 94 and is displaceable along a cylinder axis D of the cylinder 94.

[0181] Furthermore, the third conveying unit 92 comprises an actuator 98 which is illustrated merely schematically in Fig. 16 and by means of which the piston 96 can optionally be displaced along the cylinder axis D. The actuator 98 is designed such that it can actively move the piston 96 in the direction of the build space 20 when the actuator 98 is activated. Furthermore, the actuator 98 is designed such that the piston 96 can be passively displaced in a deactivated state of the actuator 98.

[0182] Furthermore, the device 10 has a blocking unit 100, by means of which the piston 96 can be locked. This means that a movement of the piston 96 can be blocked by means of the blocking unit 100. The blocking unit 100 is also illustrated merely schematically in Fig. 16.

[0183] Furthermore, the device 10 of Fig. 16 comprises a fourth container 102 for fourth material, wherein the fourth container 102 is connected in a material-conducting manner to the build space 20 in the same way as the first container 30 and the second container 44 via a fourth channel.

[0184] Furthermore, the device comprises a fourth conveying unit 104 which is designed to convey fourth material from the fourth container 102 into the build space 20.

[0185] In the illustrated embodiment, the fourth container 102 is formed as a portion of a cylinder 106 having a substantially rectangular base surface.

[0186] The fourth conveying unit 104 comprises a piston 108 which is received in sections in the inner space of the cylinder 106 and is displaceable along a cylinder axis E of the cylinder 106.

[0187] Furthermore, the fourth conveying unit 104 comprises an actuator 110 which is illustrated merely schematically in Fig. 16 and by means of which the piston 108 can optionally be displaced along the cylinder axis E.

[0188] The actuator 110 is designed such that it can actively move the piston 108 in the direction of the build space 20 when the actuator 110 is activated. Furthermore, the actuator 110 is designed such that the piston 108 can be passively displaced in a deactivated state of the actuator 110. Furthermore, the device 10 has a blocking unit 112, by means of which the piston 108 can be locked. This means that a movement of the piston 108 can be blocked by means of the blocking unit 112. The blocking unit 112 is also illustrated merely schematically in Fig. 16.

[0189] Furthermore, the device 10 of Fig. 16 comprises a fifth container 114 for fifth material, wherein the fifth container 114 is connected in a material-conducting manner to the build space 20 in the same way as the first container 30 and the second container 44 via a fifth channel.

[0190] Furthermore, the device comprises a fifth conveying unit 116 which is designed to convey fifth material from the fifth container 114 into the build space 20.

[0191] In the illustrated embodiment, the fifth container 114 is formed as a portion of a cylinder 118 having a substantially rectangular base surface.

[0192] The fifth conveying unit 116 comprises a piston 120 which is received in sections in the inner space of the cylinder 118 and is displaceable along a cylinder axis F of the cylinder 118.

[0193] Furthermore, the fifth conveying unit 116 comprises an actuator 122 which is illustrated merely schematically in Fig. 16 and by means of which the piston 120 can optionally be displaced along the cylinder axis F.

[0194] The actuator 122 is designed such that it can actively move the piston 120 in the direction of the build space 20 when the actuator 122 is activated. Furthermore, the actuator 122 is designed such that the piston 120 can be passively displaced in a deactivated state of the actuator 122.

[0195] Furthermore, the device 10 has a blocking unit 124, by means of which the piston 120 can be locked. This means that a movement of the piston 120 can be blocked by means of the blocking unit 124. The blocking unit 124 is also illustrated merely schematically in Fig. 16.

[0196] The methods previously explained by reference to the device comprising only two containers and two conveying units can also be carried out by means of the device 10 of Fig. 16. The above explanations can be applied to any pair of first material, second material, third material, fourth material and fifth material.

[0197] It is understood that even though production of a dental restoration has been explained in detail in the above examples, the device in accordance with the invention and the methods in accordance with the invention are basically suitable for producing any type of component. The methods in accordance with the invention and the device in accordance with the invention are thus not limited to the production of dental restorations.

[0198] In particular, this includes components or applications in which materials, e.g. a first material and a second material, having different properties are to be combined. For example, a mechanically efficient material can be combined with a thermal insulation layer.

[0199] Further examples of components which can be produced by means of the device in accordance with the invention and the method in accordance with the invention are patient-specific prostheses. Such components can include a flexible material for comfort and a robust or less flexible material for stability. Alternatively, such components can include a flexible material for desired mobility and a robust or less flexible material for stability or strength. This can be used e.g. in hip or knee prostheses.

[0200] Additional examples of components which can be produced by means of the device in accordance with the invention and the method in accordance with the invention include patientspecific implants, e.g. bone implants comprising a biocompatible material and a more resistant material in order to extend the useful life. Dental implants are also feasible. These can include e.g. a material, from which an aesthetic surface is created, and another material, by means of which anchoring in the bone is achieved.

[0201] Further examples of components which can be produced by means of the device in accordance with the invention and the method in accordance with the invention are patient-specific orthotics. Such components can comprise a soft, skin-friendly material for wearing comfort and a mechanically stable material for the desired support function.

[0202] Still further examples of components which can be produced by means of the device in accordance with the invention and the method in accordance with the invention are phantoms for medical imaging. Such components simulate biological tissue and for this purpose can comprise various materials. In this manner, precise imaging results can be achieved.

[0203] List of reference signs

[0204] 10 device for producing a component in layers

[0205] 12 component

[0206] 14 dental restoration

[0207] 16 core region

[0208] 18 shell region

[0209] 20 build space

[0210] 22 cylinder

[0211] 24 build platform

[0212] 26 piston

[0213] 28 curing unit

[0214] 29 transparent wall element

[0215] 30 first container

[0216] 32 first channel

[0217] 34 first conveying unit

[0218] 36 cylinder

[0219] 38 piston

[0220] 40 actuator

[0221] 42 first blocking unit

[0222] 44 second container

[0223] 46 second channel

[0224] 48 second conveying unit

[0225] 50 cylinder

[0226] 52 piston

[0227] 54 actuator

[0228] 56 second blocking unit

[0229] 58 actuator

[0230] 60 third blocking unit 62 cylindrical component

[0231] 64 flow geometry

[0232] 66 separating element

[0233] 68 first blocking slide

[0234] 70 second blocking slide

[0235] 72 excess container

[0236] 74 stopper

[0237] 88 mixing contour

[0238] 90 third container

[0239] 92 third conveying unit

[0240] 94 cylinder

[0241] 96 piston

[0242] 98 actuator

[0243] 100 blocking unit

[0244] 102 fourth container

[0245] 104 fourth conveying unit

[0246] 106 cylinder

[0247] 108 piston

[0248] 110 actuator

[0249] 112 blocking unit

[0250] 114 fifth container

[0251] 116 fifth conveying unit

[0252] 118 cylinder

[0253] 120 piston

[0254] 122 actuator

[0255] 124 blocking unit

[0256] A cylinder axis B cylinder axis

[0257] C cylinder axis

[0258] D cylinder axis

[0259] E cylinder axis F cylinder axis

[0260] Hl rectangle, denoting a cured region consisting of first material

[0261] H2 rectangle, denoting a cured region consisting of second material

[0262] Ml first material

[0263] M2 second material

Claims

Claims1. Device (10) for producing a component (12), in particular a dental restoration (14), in layers wherein at least one component layer comprises both a first material (Ml) and a second material (M2), or wherein at least one component layer is produced from the first material (Ml) and a further component layer adjacent thereto is produced from the second material (M2), comprising:- a build space (20) which is delimited by a build platform (24), which can be driven to move, and a curing unit (28) opposite the build platform (24), wherein the curing unit (28) is designed to cure first material (Ml) and / or second material (M2) present in the build space (20),- a first container (30) for first material (Ml) which is connected in a materialconducting manner to the build space (20),- a first conveying unit (34) for conveying first material (Ml) from the first container (30) into the build space (20),- a second container (44) for second material (M2) which is connected in a materialconducting manner to the build space (20),- a second conveying unit (48) for conveying second material (M2) from the second container (44) into the build space (20), wherein the first conveying unit (34) and the second conveying unit (48) are at least temporarily inversely motion-coupled and the motion coupling is mechanical and / or control technology-related.

2. Device (10) as claimed in claim 1, further comprising a mixing contour (88) for mixing the first material (Ml) and / or the second material (M2), wherein the mixing contour (88) is arranged within the build space (20) or adjacent to the build space (20).

3. Device (10) as claimed in any one of the preceding claims, further comprising a separating element (66) for keeping first material (Ml) and second material (M2) separated.

4. Device (10) as claimed in any one of the preceding claims, wherein the first container (30) is formed by means of an inner space of a cylinder (36) and wherein the first conveying unit (34) comprises a piston (38) which is received at least in sections in the inner space of the cylinder (36) and is displaceable in the inner space, and / or wherein the second container (44) is formed by means of an inner space of a cylinder (50) and wherein the second conveying unit (48) comprises a piston (52) which is received at least in sections in the inner space of the cylinder (50) and is displaceable in the inner space.

5. Device (10) as claimed in any one of the preceding claims, wherein the motion coupling is hydromechanical via the first material (Ml) and / or via the second material (M2), or wherein the first conveying unit (34) and the second conveying unit (48) are mechanically coupled, or wherein the first conveying unit (34) and the second conveying unit (48) are mechanically separate from one another and are coupled in terms of control technology.

6. Device (10) as claimed in claim 5, wherein the build platform (24), the first conveying unit (34) and the second conveying unit (48) can be selectively and individually locked in order to motion-couple in each case two of the build platform (24), the first conveying unit (34) and the second conveying unit (48) hydromechanically via the first material (Ml) and / or via the second material (M2).

7. Device (10) as claimed in any one of the preceding claims, wherein the build platform (24) is designed as an end surface of a piston (26) guided in a cylinder (22).

8. Device (10) as claimed in any one of the preceding claims, further comprising an excess container (72) for receiving excess first material (Ml) and / or excess second material (M2), wherein the excess container (72) is connected in a material-conducting manner to the build space (20).

9. Method for producing a component (12), in particular a dental restoration (14), in layers, wherein at least one component layer comprises both a first material (Ml) and a second material (M2), comprising:- providing a layer of uncured first material (Ml) and curing at least a portion of the layer so that the layer comprises a region of cured first material (Ml) and a region of uncured first material (Ml),- replacing the uncured first material (Ml) in the layer with uncured second material (M2) so that the layer comprises a region of the cured first material (Ml) and a region of the uncured second material (M2), and- curing at least a portion of the layer which comprises second material (M2) so that the layer comprises a region of cured first material (Ml), a region of cured second material (M2), and a region of uncured second material (M2).

10. Method as claimed in claim 9, wherein the uncured first material (Ml) in the layer is replaced by uncured second material (M2) by displacement of the uncured first material (Ml) by means of uncured second material (M2).

11. Method as claimed in claim 9 or 10, further comprising producing a flow geometry (64) for first material (Ml) by locally curing the second material (M2) and / or producing a flow geometry (64) for the second material (M2) by locally curing first material (Ml) and / or by uncured first material (Ml) and / or uncured second material (M2) flowing around a flow geometry.

12. Method as claimed in claim 11, wherein the flow geometry (64) for first material (Ml) delimits a region, in which first material (Ml) is to be cured, at least in sections, and / or comprises a flow channel for first material (Ml) and / or wherein the flow geometry (64) for second material (M2) delimits a region, in which second material (M2) is to be cured, at least in sections and / or comprises a flow channel for second material (M2).

13. Method as claimed in any one of claims 9 to 12, further comprising removing excess uncured first material (Ml) and / or excess uncured second material (M2).

14. Method for producing a component (12), in particular a dental restoration (14), in layers, wherein at least one component layer comprises both a first material (Ml) and a second material (M2), comprising:- providing uncured first material (Ml) and uncured second material (M2) within a layer,- mixing the uncured first material (Ml) and the uncured second material (M2) within the layer, and - curing at least a portion of the mixture of uncured first material (Ml) and uncured second material (M2) within the layer.

15. Method as claimed in claim 14, wherein the uncured first material (Ml) and the uncured second material (M2) are mixed by moving a contact surface present between the uncured first material (Ml) and the uncured second material (M2) within the layer.

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