Decorative surface production

Abstract

The invention relates to a method for producing a decorative surface on a workpiece (1), said method comprising the following steps: - step (S1): providing a workpiece (1) with a workpiece surface (1a) on which a base decoration (2) is located; - step (S2): detecting the base decoration (2) on the workpiece surface (1a) using a detection device (20); - step (S3): measuring the detected base decoration (2); - step (S4): providing a target additional decoration template (200) for an additional decoration (3), the target additional decoration template (200) being synchronous with a target base decoration (150); - step (S5): adapting the target additional decoration template (200) on the basis of the measured base decoration so as to obtain an adapted target additional decoration template (200') according to which the additional decoration can be applied at least partially synchronised with the base decoration; - step (S6): using an application device (30) to apply the additional decoration (3) to the workpiece (1) above the base decoration (2) in accordance with the adapted target additional decoration template (200'). The invention also relates to a device for carrying out the method.

Description

[0001] The present invention relates to a method for producing a decorative surface on a workpiece and to a device for carrying out the method.

[0002] The present invention relates in particular to a method and a device for producing an optically and / or haptically structured surface on a workpiece. The workpiece provided with the decorative surface can be used to create a desired design. For example, the workpiece can be used as a floor panel, a furniture panel, or as a panel for tables, cabinets, wall and / or ceiling cladding. Another possible application is a panel for the exterior cladding of facades, e.g., building exterior walls. Typically, different decorative elements must be precisely aligned, i.e., synchronously, on top of each other on the workpiece. The decorative elements can be either two-dimensional or three-dimensional.

[0003] In particular, the invention deals with the problem of applying a second decoration (additional decoration) to a workpiece synchronously with a first decoration (base decoration).

[0004] A typical application is the creation of a synchronous structure with raised areas and / or depressions, usually less than one millimeter in height, on a surface already decorated with a two-dimensional pattern, such that the raised areas and depressions are synchronized with the underlying decorative layer (base pattern). An example of such a design is a panel printed with a wood grain pattern, where a corresponding depression is created in the area of ​​printed (represented) knots. Another example is a tile surface where the grout lines between the tiles are slightly recessed using this method, while the individual tiles themselves are raised in comparison.

[0005] Methods for producing workpieces with decorative surfaces are already known. One notable example is patent EP 3 109 056 A1, which discloses a method for creating three-dimensional structures in combination with a decorative image. This involves applying a base decoration and an additional decoration to a workpiece to form a decorative surface. The decorative image can be the base decoration, with the three-dimensional structure then acting as the additional decoration and positioned above the base decoration on the workpiece. However, the reverse is also conceivable, where the three-dimensional structure acts as the base decoration and the decorative image is positioned above the structure as the additional decoration.

[0006] The application of the additional decorative layer without considering the actual geometry of the base decorative layer is problematic when synchronization between the two is required. A typical application is the production of a decorative surface that imitates a wood surface, featuring wood grain and knots as decorative elements. The structure of this decorative layer is usually such that a base decorative layer, in this case a two-dimensional image of the wood surface, is applied to the workpiece surface, and an additional decorative layer, representing the three-dimensional wood structure, is applied on top of this base decorative layer. Ideally, the additional decorative layer should be applied in such a way as to ensure synchronization with the base decorative layer, even if the base decorative layer is distorted, rotated, or shifted on the workpiece surface.

[0007] Synchronicity here means that misalignment between the base and additional decorations is minimized. Both the base and additional decorations are designed as complementary designs. This means they are coordinated so that when applied to the workpiece, they create a harmonious overall design. A misalignment occurs when parts of the base and additional decorations are not positioned correctly, resulting in a visual flaw in the combined design.

[0008] Since errors or inaccuracies can occur during the application of the base decoration to the workpiece, a misalignment can result if the additional decoration is applied without taking these errors into account. Errors in the base decoration can occur, for example, due to stretching of a film, such as a PVC film bearing the base decoration, during lamination onto the workpiece. If the base decoration is applied using a printing process (analog or digital), errors in the printing process or incorrect workpiece orientation can also introduce flaws into the base decoration.

[0009] In general, such registration errors can always occur when there are measurable deviations between a target base decor (as designed analogously or digitally) and the actual base decor as measured on the workpiece after the base decor has been applied. For example, if a tile design has a print length of 1,430 mm as the base decor, and a printed length of 1,433 mm is measured on the substrate (roll material, sheets, or similar) after printing, a corresponding printing error exists. If an additional decor with a length of also 1,430 mm is then applied to the base decor, there is no registration error only in the unrealistic case that the exact same error occurs in the second printing process as in the first. In all other (much more likely) cases, a registration error will occur.If, for example, the base decor is laminated and the additional decor is applied using digital printing, two different processes are used, which increases the likelihood of a mismatch.

[0010] In this context, US 2014 / 017452 A1 concerns building panels, in particular floor panels, and a method for manufacturing such building panels that have a decorative surface and a transparent protective layer applied by digital coating. A digital print or digital embossing can be adapted to a specific panel surface using an image processing system.

[0011] DE 10 2012 103491 A1 relates to a process for producing a structured, at least partially optically transparent lacquer surface on a decorative surface of a carrier board, in which transparent or at least partially transparent lacquer is applied to an application roller to create the structured lacquer surface and transferred to the decorative surface of the carrier board by means of the application roller, and in which the lacquer is applied to the application roller in a structure-defining distribution by means of a multitude of digitally controlled nozzles and / or transformed on the application roller into a structure-defining distribution.

[0012] DE 10 2013 101521 B4 relates to a surface element comprising at least one material layer with a structured surface and at least one visible surface applied thereon, wherein an image of a master pattern is applied to the structured surface of the material layer, and wherein the position of the applied image is aligned with the structured surface such that corresponding elements in the image and the structured surface coincide with each other. The structured surface of the material layer was created using the master pattern or the impression plate produced on the basis of the master pattern.

[0013] EP 2 507 063 B1 relates to a method for producing a three-dimensional surface structure on a workpiece by feeding a workpiece printed with a decorative image to a processing station, spraying a transparent, radiation-curing lacquer through a multitude of nozzle openings onto the surface of the workpiece in the form of lacquer droplets and curing the transparent lacquer with radiation.

[0014] The object of the present invention is to demonstrate a way to ensure that the synchronous application of the additional decoration to the base decoration can be ensured, especially if a deviation between the intended base decoration and the actually printed base decoration, e.g. in length, width, elongation or compression, has already occurred during the application of the base decoration.

[0015] This task is solved by the subject matter of the independent claims. Advantageous further developments are the subject matter of the dependent claims.

[0016] According to the invention, a method for producing a decorative surface on a workpiece is provided. The method comprises the following steps: Step S1: Providing a workpiece with a workpiece surface on which a base decoration is located; Step S2: Capturing the base decoration on the workpiece surface with a capturing device; Step S3: Measuring the captured base decoration; Step S4: Providing a target additional decoration template for an additional decoration, wherein the target additional decoration template is designed synchronously with a target base decoration; Step S5: Adapting the target additional decoration template based on the measured base decoration so that an adapted target additional decoration template is available according to which the additional decoration can be applied at least partially synchronously with the base decoration; Step S6: Applying the additional decoration to the workpiece above the base decoration according to the adapted target additional decoration template with an application device.

[0017] Preferably, at least one of steps S3, S4, and S5 is performed by a data processing device. This enables automated execution of the procedure.

[0018] The method according to the invention is particularly intended to be carried out by a device that processes the workpiece continuously. This means that several workpieces can be processed successively in an industrial manner.

[0019] Essentially, the base decor already on the workpiece is analyzed by scanning and measuring it so that the additional decor can then be applied synchronously with the base decor, or with minimal mismatch, based on the target additional decor template adapted according to step S5. This results in the additional decor being adapted to the actual base decor (actual base decor). If the actual base decor is applied flawlessly to the workpiece surface, it corresponds to the target base decor.

[0020] The process described here can significantly reduce production rejects and improve production quality. For example, if a base decor is present on the workpiece surface where exact alignment, proportion, and / or position relative to the workpiece is not strictly necessary—since, for the observer, the precise location of the base decor elements on the workpiece surface is irrelevant for recognizing the base decor—then applying the additional decor according to the adapted target additional decor template ensures synchronization between both decors (base decor and additional decor). This prevents the workpiece from being rejected as scrap despite defects or errors in the existing base decor. An example of this is the imitation of a natural product, such as a wood surface. Here, for instance, a two-dimensional image of the wood decor is used.The wood surface is used as a base decoration. This means it is a representation of an irregular and naturally textured pattern, whose decorative elements exhibit varying characteristics and can be designed as knots, grooves, notches, but also flat sections and color variations. Even if such a base decoration is not applied to the workpiece surface as desired, according to a specific orientation, proportion, and / or position, this is irrelevant to the observer, at least up to a certain point defined by aesthetic criteria, because the observer will always recognize a wood pattern, as corresponding decorative elements that determine the overall impression of the wood pattern are present. The actual orientation, proportion, and / or position does not detract from the overall impression of a wood pattern.Rather, one can even assume that a viewer will expect to see non-repeating patterns in such a wood decor, which is also the case with real wood. If a corresponding additional decor is applied to this base decor, which is a three-dimensional structure that actually replicates the decorative elements, the resulting feel of the workpiece surface changes from a flat surface to an actual, three-dimensionally designed wood structure. A decorative element of the base decor (e.g., an image of a knot) aligns with the corresponding decorative element of the additional decor (e.g., a three-dimensional knot structure). This means that both decorative elements are now arranged synchronously, since the desired additional decor template has been adapted to the base decor on the workpiece.

[0021] The term "proportion" can be understood as a description of an elongation and / or compression and / or rotation of the corresponding decoration, particularly in the x-direction and / or in the y-direction (i.e., transverse to the feed direction and / or in the feed direction). This can extend over the entire decoration or only over a section of it.

[0022] "Alignment" refers to the overall orientation of the decor. That is, whether the decor is oriented in the desired direction or rotated as a whole. If there are discrepancies between the intended and actual orientation, this constitutes an alignment deviation.

[0023] The "position" describes the location where the corresponding decoration is positioned. If there are discrepancies between the target and actual positions, then there is a positional deviation.

[0024] Besides wood decors, other decors are also conceivable, which can be created by combining a base decor and additional decor. In particular, tile decors and other natural decors, such as stone floors, should be mentioned here.

[0025] The method is preferably carried out such that the adapted target template is created directly for application of the additional decoration by the application device. That is, if the method is performed in a device that applies the additional decoration to the workpiece after capturing and measuring the base decoration (for example, during continuous machining of the workpiece), it is sufficient to provide the target template for the additional decoration or to store it in memory. This template is then individually adapted to the base decoration actually present on the workpiece. It is preferably provided that the adapted target template for the additional decoration is not permanently stored, but merely provided to the application device as a data record. A volatile data storage device, such as the working memory, can be used for this purpose.Alternatively or additionally, it is of course conceivable to permanently save the adapted target additional decoration template, for example to document production.

[0026] A synchronous application of base decor and additional decor preferably results in a deviation of individual decorative elements that is less than + / - 3 millimeters, preferably less than + / - 1 millimeter, and particularly preferably less than + / - 0.5 millimeters.

[0027] Essential for adapting the target additional decoration template is the detection of the base decoration (actual base decoration) on the workpiece surface in step S2. A detection device is preferably used for this purpose.

[0028] In step S3, information about the target base decor is provided, and any deviation of the actual base decor from the target base decor is determined by comparing the measured base decor with the target base decor. This means that measuring the measured base decor leads to the identification of differences from the target base decor. This can be done, in particular, by comparing target positions with actual positions of marks, decorative elements, and / or an edge of the base decor.

[0029] Providing information about the target base decor can be achieved, for example, by providing a digital data set. This can be, in particular, a digital data set that serves as the template for applying the base decor to the workpiece surface. For a two-dimensional base decor, this could be an image file. For a three-dimensional base decor, such an image file, or a file that describes the target base decor in the plane, can be enriched with additional information that also describes the target base decor's upward extension. That is, it can include a height profile.

[0030] The information about the target base decor can also be provided in a significantly reduced form. For example, this can include the specification of target positions for one or more marks of the base decor, at least one edge of the base decor, and / or individual decorative elements of the base decor, or even the base decor as a whole. The base decor property that is then determined—that is, in particular, the orientation, proportion, and / or position of the actual base decor on the workpiece surface—can be determined by comparing the correspondingly recorded marks of the base decor, at least one edge of the base decor, and / or decorative elements of the base decor on the workpiece surface. The entire base decor can also be compared with the entire target base decor.

[0031] In this case, the basic decor property is therefore not an absolute specification of, for example, orientation, proportion and / or position of the actual basic decor, but instead a specification relative to a target basic decor, which is characterized by at least one target basic decor property.

[0032] The data is preferably captured without contact, in particular optically.

[0033] One option for optical detection is to capture the base decoration with a camera that is part of the detection system. This means that the workpiece surface on which the base decoration is located is captured with a camera, and the captured information is converted into an image file. A camera can be used that captures the base decoration in its entirety or only a section of it. Furthermore, it is also conceivable that the base decoration could be captured in the non-visible light spectrum.

[0034] Both two-dimensional and three-dimensional base decorations can be captured with a camera. While with a two-dimensional base decoration, it is conceivable to capture the color or the decorative elements formed from it, with a three-dimensional base decoration, in addition to camera capture, it is also possible to capture reflections or shadows of the decoration created by a light source within the capture device, directed at the base decoration and emitting light in its direction. The image of reflections and / or shadows of the base decoration captured by the camera can then be digitally stored as information about the base decoration.In particular, a light source can emit light or electromagnetic radiation at an angle of less than 90 degrees, preferably less than 60 degrees, to the surface of the workpiece, and the detection device can also be aligned at such an angle to the surface of the workpiece. Reflections and / or shadows can be used, especially with a three-dimensional base decoration, to determine individual flanks of the three-dimensional structure or to determine its height. If the base decoration is detected with a camera of the detection device, a light source of the detection device can also be used that emits non-visible light (UV light or IR light), which then causes special reflections of the base decoration that can be detected by the camera.Another way to generate reflections and / or shadows of the base decoration and capture them as information about the base decoration is by using a laser through the detection device, which is directed at the base decoration as a light source.

[0035] When capturing the base decor non-contact, especially optically, it is also conceivable to capture the base decor with multiple capture devices. These devices can capture the base decor from the same angle and / or from different angles. This is particularly useful for a base decor that exhibits a different appearance depending on the viewing angle, in order to gather a sufficient information or data basis for measuring the base decor according to step S3. Especially with a three-dimensional base decor that has raised areas and / or recesses, it is advisable to capture the base decor from different angles.

[0036] Alternatively or additionally, the base decor can be detected capacitively or inductively using a detection device equipped with appropriate sensors. If the base decor is designed in such a way that it allows for changes in electric or magnetic fields in sections within such a sensor, then the base decor can also be detected using these sensors.

[0037] Furthermore, alternative or additional methods for capturing the base decor are possible. For example, capture can also be performed with a detection device that has a touch sensor, which can, for example, capture a height profile of a three-dimensional base decor or which can detect certain components of the base decor by touch, such as electrically conductive or magnetic decorative elements.

[0038] In addition to the basic decor or individual basic decor elements, specially designed elements of the basic decor can also be recorded, such as marks or borders of the basic decor.

[0039] The positions of the basic decorative elements and / or the marks and / or the edges of the basic decor are particularly favored as a result.

[0040] Preferably, the orientation and / or position of the workpiece itself, which bears the base decoration, is determined or predetermined before detection or measurement. Detection can be performed in the same manner as the detection of the base decoration. Predetermining the orientation and position of the workpiece can be done mechanically, for example, by guide devices that align the workpiece accordingly while it is being transported in a feed direction. Alternatively, aligning a clamping device that secures the workpiece is also conceivable.

[0041] Preferably, the capture of the base design in step S2 includes the capture of marks of the base design. Alternatively or additionally, the capture of the base design in step S2 includes the capture of at least one border of the base design. Alternatively or additionally, the capture of the base design in step S2 includes the capture of at least one decorative element of the base design. In particular, the capture of the base design in step S2 can consist exclusively of the capture of marks, at least one border of the base design, and / or at least one decorative element of the base design.

[0042] The markings or border are applied to the workpiece surface using the same process as the base decoration itself. This ensures that information about the orientation, proportion, and / or position of the base decoration can be derived from the detection of the corresponding markings or border, because defects in the markings and / or border of the base decoration also allow conclusions to be drawn about defects in the entire base decoration.

[0043] Preferably, several of the marks and / or decorative elements are detected and measured. Preferably, at least two, more preferably four, and in particular 16 marks and / or decorative elements are detected and measured. If at least three marks and / or decorative elements are detected and measured, it is advantageous if they do not lie on a straight line, so that the extent of the base decoration on the workpiece surface can be measured in two dimensions.

[0044] Marks can be intended to be invisible markings on the workpiece or base decoration. This means they are not visible to the human eye and therefore do not detract from the overall aesthetic appearance of the finished workpiece. These marks can be capacitively or inductively detectable, or they can emit or reflect light in the non-visible wavelength range. A suitable detection device can then detect these marks.

[0045] Preferably, in step S3, i.e., during the measurement of the base decoration, information about the orientation, proportion, and / or position of the base decoration on the workpiece surface is determined. This establishes an actual base decoration property, which then serves as the basis for adapting the additional decoration template.

[0046] If an error is introduced into the base decoration during its application, such as elongation (which corresponds to a change in proportion), this can be detected because the distance between two corresponding marks is now larger than a reference or target value, such as that specified by the target base decoration. Consequently, the actual measured base decoration on the workpiece surface no longer corresponds to the target base decoration in all dimensions. In addition to elongation, compression or stretching in the x-direction (perpendicular to the workpiece feed direction) as well as in the y-direction (in the feed direction), and combinations of these errors can also occur during the application of the base decoration.Actual base decor properties such as orientation, proportion, and / or position can therefore be determined by examining individual elements, such as marks, a border, or even individual decorative elements of the base decor. To identify deviations, marks, a border, or even individual decorative elements of the base decor can then be compared with a target base decor, as explained further below.

[0047] Marks can be positioned inside or outside the area covered by the base decoration on the workpiece surface. If they are positioned inside the base decoration, they can function as a permanent part of it, so that they later blend aesthetically into the base decoration and act as base decoration elements. Alternatively, they can be removed in a later step.

[0048] The markers are preferably positioned so that their detection provides or enables information about the orientation, proportion, and / or position of the base design. For example, two markers can be used to determine whether the distance between them corresponds to an expected distance, such as that specified by a target base design, or whether there is a compression (distance too small) or stretching (distance too large) of the base design in the direction of extension between these markers.

[0049] If three markers are present that are not placed on a common straight line, a compression or stretching between each pair of markers can be determined. If four markers are present that together form the vertices of a quadrilateral, preferably a rectangle or square, a two-dimensional base decoration can be captured relatively accurately in its length and width. However, it is also possible to use the detection of the markers to capture a three-dimensional base decoration in its length and width. For example, a marker may be positioned at a specific location that corresponds to a particular three-dimensional decorative element. Thus, by detecting this marker alone, the position of the corresponding decorative element can be determined.

[0050] Furthermore, multiple marks can be individually customized so that they can be distinguished from one another when measuring the captured base decor. For example, marks can be visually differentiated by having different shapes and / or colors. They can also be designed to be readable by the scanning device or a data processing device used to perform step S3, for example, by having a barcode, a QR code, and / or lettering. It is also conceivable to design marks to be electronically readable, for example, by enabling them to transmit information, as is possible with RFID chips. By designing the marks so that they are readable by the scanning device or the data processing device, or so that they contain readable information, it is possible to identify the marks during the measurement process.Furthermore, it is also possible to equip marks with additional readable information. For example, based on this readable information, a target base decor can be retrieved from a database of target base decors and assigned to the base decor actually present on the workpiece surface.

[0051] If the base decoration has a border, then the border, or at least one border, of the base decoration can also be used to capture the base decoration and, in particular, to determine information about its orientation, proportion, and / or position. The border of the base decoration can be a visible line or a line invisible to the human eye and detectable only by the capture device. In the case of a three-dimensional base decoration, it can also be an edge. Furthermore, it is possible for the border to be removed in a later processing step, i.e., after capture. Figures 1a and 1bFurthermore, they demonstrate how various properties of a base decoration can be determined from the measurement of its edge. For this, please refer to the corresponding description below.

[0052] Ultimately, capturing decorative elements of the base decor is equivalent to capturing marks. A decorative element thus functions as a mark and, particularly in combination with other decorative elements or marks, can be used to determine properties such as orientation, proportion, and / or position of the base decor, as described above.

[0053] Advantageously, the base decor is captured, measured, and at least one base decor property is determined from this. Thus, this at least one base decor property provides information about, for example, the orientation, proportion, and / or position of the base decor on the workpiece surface. This is essential for the further execution of the process, because the information about the base decor now provides the basis for adapting a target additional decor template with respect to at least one additional decor property, such as the orientation, proportion, and / or position of the additional decor. In other words, the target additional decor template is now adapted to the actual base decor present on the workpiece surface (actual base decor) to achieve synchronous alignment of the base decor and the additional decor. If, for example, the measurement reveals that the base decor is rotated, i.e.,If the base decoration is not applied to the workpiece surface in the correct orientation, the corresponding target additional decoration template is adjusted accordingly so that the additional decoration is applied rotated, thus restoring synchronization between the two decorations. For example, if the measurement reveals that the base decoration is distorted, i.e., not in the correct proportion, applied to the workpiece surface, the corresponding target additional decoration template is adjusted so that the additional decoration is applied with the corresponding distortion, thus restoring synchronization between the two decorations. Similarly, if the measurement reveals that the base decoration is incorrectly positioned, i.e., not applied in the correct position on the workpiece surface, the corresponding target additional decoration template is adjusted so that the additional decoration is applied in the position of the base decoration, thus restoring synchronization between the two decorations.It is understood that the base decor may also have errors in at least two of the properties of orientation, proportion, and position, or even in all three properties. In such cases, the target additional decor template is adjusted accordingly to restore synchronization between the two decors.

[0054] Advantageously, information about the height of the base decor, or its height profile, is also determined when measuring the base decor. This is particularly beneficial for base decors with a three-dimensional structure. In this way, the base decor actually present on the workpiece surface can be described not only in terms of its length and width, and thus especially with regard to its orientation, proportion, and position, but also in terms of its height profile. This is particularly relevant when the height profile of a base decor to be printed is altered in such a way that the area onto which the additional decor is to be applied differs in size from the expected area of ​​a target base decor, i.e., it is larger or smaller. For example, consider a base decor element that tapers upwards, i.e., away from the workpiece surface. This could be a cone or a pyramid, or...The base decorative element could be a truncated cone or a truncated pyramid. If an additional decoration is to be applied to such a base decorative element, it may be stipulated that material for the additional decoration is also applied to the side surfaces of the base decorative element, for example, to the lateral surface of the cone or truncated cone, or to the side surfaces of the pyramid or truncated pyramid. If the corresponding base decorative element is taller or shorter than the intended base decorative element, the side surface or lateral surface will be correspondingly larger or smaller. In any case, the amount of material required for the additional decoration will differ from the amount that would actually be required based on the unadjusted intended additional decoration template. The recorded height profile thus provides information about the actual height of the base decorative element.Based on the actual height of the base decorative element, the actual surface area of ​​the base decorative element, and thus the actual amount of material required to create the additional decorative element, can be determined at least approximately using mathematical models. The material quantity determined in this way can then be incorporated into the adapted target additional decorative element template, after which the additional decorative element is applied. This allows for adjustments to be made to compensate for irregularities in the height profile of the base decorative element.Otherwise, there would be a risk that, for example, if the base decorative element is too high, it would not be possible to completely cover the base decorative element with the additional decoration, or that if the base decorative element is too low, too much material would be applied to the base decorative element, which would result in the contour of the base decorative element being altered, since the material for the additional decoration would more even out the contour of the base decorative element.

[0055] According to an advantageous embodiment of the invention, the template for the additional decorative element has adaptation elements that correspond in position to corresponding synchronization elements of the base decoration on the workpiece, or that must maintain a specific distance from the corresponding elements of the base decoration in order to apply the additional decoration synchronously with the base decoration. The synchronization elements are preferably detected during the detection of the base decoration and subsequently measured so that their position is known. The adaptation of the template for the additional decorative element to the actual base decoration is then carried out by moving the adaptation elements of the template so that the required distances to the synchronization elements are achieved. It is preferably provided that a synchronization element corresponds to a mark, a border, and / or a base decoration element.

[0056] Preferably, the base decor is captured pixel-based in step S2 and / or measured pixel-based in step S3. This is particularly advantageous when the additional decor is applied pixel-based, for example, using a digital printing medium such as a digital printhead or a digital print bar. Deviations of the base decor from a target state, especially from a target base decor, can thus be described with pixel-level precision. It is particularly advantageous if the pixel-based capture and / or measurement of the base decor is performed at the same resolution as the target additional decor template. This allows a deviation of the base decor from the target state to be directly translated into corresponding pixel deviations. These pixel deviations, which can be represented as displacement vectors, then represent a deviation of individual pixels of the base decor from the target state.The same displacement vectors can then be used in step S5 to shift and thus adjust the pixels of the target additional decoration template. If the resolution at which the base decoration is captured in step S2 and / or measured in step S3 differs from the resolution of the target additional decoration template, an adjustment can be made. This can be done by adjusting the pixel resolution after step S2, or in or after step S3, to the resolution of the target additional decoration template. Alternatively, the determined displacement vectors can also be adjusted.

[0057] Instead of capturing each pixel of the base decor separately in step S2 and / or measuring it in step S3, it is also possible to determine the displacement vectors using the methods described above. That is, if information about individual marks, decorative elements, and / or an edge of the base decor is captured, it is possible to infer, among other things, the orientation, proportion, and / or position of other decorative elements of the base decor or of the base decor as a whole. This can be calculated, at least approximately, using mathematical models. For example, if two marks or decorative elements are captured whose distance has been increased by a certain percentage, then, assuming that the change in distance was uniform, the following can be determined for pixels:Decorative elements lying on the line connecting these two markers or decorative elements are assumed to undergo a uniform and steadily increasing shift along the line. That is, if the distance between the two markers or decorative elements is increased by 20%, a pixel or decorative element that should be located at 25% of the connecting distance will be shifted by 5% along the connecting line. A pixel or decorative element that should be located at 50% of the connecting distance will be shifted by 10% along the connecting line. Finally, a pixel or decorative element that should be located at 75% of the connecting distance will be shifted by 15% along the connecting line. This is, of course, only one example of how to determine the shifts.

[0058] Alternatively or additionally, to adapt the target additional decoration template, a pixel from the unadapted target additional decoration template is read and moved to a new position. This means that the information (such as the quantity of printing material, ink, etc.) that was contained at this pixel position for applying the additional decoration is moved to a new position as part of the target additional decoration template adaptation. It is possible that the information is transferred exactly, i.e., simply moved to a different pixel in a different location. However, it is also possible that the information for a pixel in the adapted target additional decoration template is calculated from several originally existing pixels in the unadapted target additional decoration template, or that the information of a pixel from the unadapted target additional decoration template is now distributed across several pixels in the adapted target additional decoration template.

[0059] Preferably, the information about the target base decor is provided as a digital data set.

[0060] For example, the target base decor property can thus be read by a control unit.

[0061] Providing information about the target base decor can be achieved, for example, by providing a digital data set. This can be, in particular, a digital data set that serves as the template for applying the base decor to the workpiece surface. For a two-dimensional base decor, this could be an image file. For a three-dimensional base decor, such an image file, or a file that describes the target base decor in the plane, can be enriched with additional information that also describes the target base decor's upward extension. That is, it can include a height profile.

[0062] The information about the target base decor can also be provided in a significantly reduced form. For example, this can include the specification of target positions for one or more marks of the base decor, at least one edge of the base decor, and / or individual decorative elements of the base decor, or even the base decor as a whole. The base decor property that is then determined—that is, in particular, the orientation, proportion, and / or position of the actual base decor on the workpiece surface—can be determined by comparing the correspondingly recorded marks of the base decor, at least one edge of the base decor, and / or decorative elements of the base decor on the workpiece surface. The entire base decor can also be compared with the entire target base decor.

[0063] In this case, the basic decor property is therefore not an absolute specification of, for example, orientation, proportion and / or position of the actual basic decor, but instead a specification relative to a target basic decor, which is characterized by at least one target basic decor property.

[0064] Preferably, the information about the target base decor is provided as a digital data set.

[0065] For example, the target base decor property can thus be read by a control unit.

[0066] For example, the data set provided in this way may only contain data on the desired orientation, proportion, and / or position of the marks or individual decorative elements of the base design. However, other properties may also be present in this data set. In particular, if the base design has a two-dimensional pattern, image information may be stored as an image file in the data set. If the base design has a three-dimensional shape, a height profile may be stored in addition to its horizontal extent.

[0067] Preferably, the result of the measurement according to step S3 and / or the target additional decoration template is provided as a digital data set. These data sets can also be processed by a control device. The target additional decoration template can be used to control a device to apply the additional decoration. The target additional decoration template is only modified in its contained information by the adjustment according to step S5, not structurally. This means that the adjustment according to step S5 ultimately only results in the application of the additional decoration according to step S6 now proceeding differently compared to application according to an unadjusted target additional decoration template.

[0068] Preferably, step S5 includes adjusting at least the orientation, proportion, and / or position of the target additional decorative template. In summary, based on the detected base decorative property, at least one additional decorative element is adjusted so that there is again a synchronous alignment between this decorative element and the corresponding element of the base decorative.

[0069] Alternatively or additionally, step S5 can include shifting adjustment elements of the target additional decor template according to the base decor to align the target additional decor template with the base decor. Adjustment elements can be specific areas of the target additional decor template, such as decorative elements. However, they can also describe a specific area of ​​the target additional decor template. In particular, this could be specific pixels or a specific pixel structure of the target additional decor template. Once the target base decor and the target additional decor template are aligned, a specific distance between corresponding elements of the base decor and the adjustment elements is defined. These elements of the base decor are subsequently referred to as synchronization elements.In particular, it may be stipulated that the synchronization elements must be congruent with the adaptation elements to ensure synchronization between the base decoration and the additional decoration. Alternatively, it may be stipulated that a specific distance must be set between the synchronization element and the adaptation element. The synchronization elements of the base decoration may be marks, a border, and / or decorative elements of the base decoration mentioned above.

[0070] After completing step S3, i.e., measuring the base decor, the position of these synchronization elements on the workpiece surface can be obtained. The adjustment of the target additional decor template according to step S5 can then be carried out such that, by coordinating the target base decor and the unadjusted target additional decor template, predefined distances between the synchronization elements and the adjustment elements are known and must be set. These distances are preferably zero, meaning that a corresponding adjustment element should be positioned synchronously with a corresponding synchronization element, i.e., in this case, perfectly congruently. By shifting the adjustment elements towards the synchronization elements, a shift of further elements of the additional decor can be derived. Preferably, this is done using mathematical models by determining displacement vectors for individual elements of the target additional decor template.If the target additional decoration template is pixel-based, displacement vectors for all pixels of the target additional decoration template can be determined in this way.

[0071] By shifting the adjustment elements and, in particular, by generating shift vectors, the target additional decor template is adjusted in alignment, proportion and / or position.

[0072] Preferably, the base decoration comprises a two-dimensional decorative image and / or a three-dimensional structure. According to a particular embodiment, the base decoration consists of a two-dimensional decorative image and / or a three-dimensional structure. Alternatively or additionally, the supplementary decoration comprises a two-dimensional decorative image and / or a three-dimensional structure. According to a particular embodiment, the supplementary decoration consists of a two-dimensional decorative image and / or a three-dimensional structure.

[0073] Preferably, step S6 comprises applying the additional decoration using a digital application method, an analog application method, or a hybrid application method. All of these application methods can be configured to apply the additional decoration as a two-dimensional decoration or as a three-dimensional structure. These application methods can be specifically designed as printing methods and / or structuring methods. A printing method produces a two-dimensional decoration, i.e., a decorative image, while a structuring method produces a three-dimensional structure.

[0074] A digital printing or structuring process is understood to mean, in particular, an application process in which a digital printer, i.e. an inkjet printer, is used.

[0075] An analog printing or structuring process is characterized by analog printing means, such as a roller that rolls on the workpiece surface.

[0076] A hybrid printing or structuring process is characterized by a combination of digital and analog printing or structuring methods. For example, a printing roller is used that rolls across the workpiece surface, with a digital printer used before and / or after.

[0077] When creating a two-dimensional decoration, material, preferably in different colors, such as ink, is applied to the workpiece. In a digital printing process, this is usually done drop by drop. In an analog printing process, this is done by transferring the material to the workpiece using an analog printing medium, such as a roller.

[0078] A three-dimensional structure can also be created in different ways.

[0079] If a positive build-up of the structure is chosen, material is applied to the workpiece in layers, with varying thicknesses in different areas to create a three-dimensional structure. In a digital structuring process, structural material is applied drop by drop to the workpiece, with varying amounts of material being applied to different positions. This creates a three-dimensional structure with raised areas and depressions. This is an additive process. In an analog structuring process, to create a positive build-up, at least two layers of material are applied using coating rollers or other coating methods, with the upper layer not completely covering the lower layer in certain areas. This also allows for the creation of depressions.

[0080] If a negative build-up is chosen, a three-dimensional structure can be created by introducing depressions into a previously applied liquid or gelled base layer. In a digital structuring process, material is thus applied drop by drop onto a previously applied and at least not yet completely cured base layer. Various methods are conceivable for forming the depressions. For example, the base layer can be displaced by the momentum of the droplets. Alternatively, the droplets can simply penetrate the base layer or come to rest on it, thereby influencing a subsequent curing step in such a way that the base layer material does not fully cure and can then be removed, while the surrounding base layer material is cured and remains on the workpiece as a three-dimensional structure.In an analogous structuring process, indentations are embossed into a base layer using embossing tools such as embossing rollers or embossing plates to create a negative structure, thus forming the three-dimensional structure. Structures can therefore also be represented using this method.

[0081] Preferably, the adapted target decorative template is used to control the application method employed.

[0082] If the application process is digital, the target decorative element template is contained in a digital data set that can be used to control the droplet application. This means that the droplet application is controlled so that the decorative element is synchronized with the underlying base decoration. This applies to both two-dimensional and three-dimensional decorative elements. In particular, the adapted target decorative element template enables pixel-precise droplet application.

[0083] If the application method is analog, the flexibility offered by digital methods, which stems from the relatively free placement of the droplets, is not available. Analog printing media, such as a printing roller, as well as embossing media, such as an embossing roller or embossing plate, are designed to roll on the workpiece surface; that is, the relative velocity between the surface of the printing media or embossing media on the one hand and the workpiece on the other is zero. However, by changing the control of the printing media or embossing media, or by using a transport device that moves the workpiece past the printing or embossing media, a sliding motion between the printing media or embossing media and the workpiece can be achieved. In this way, the position and proportion in the longitudinal direction, i.e., in the rolling direction of the roller or embossing media, can be adjusted.The conveying direction of the workpiece can be changed, and the additional decoration can be applied accordingly, adapted to the base decoration.

[0084] A corresponding target decoration template, or a suitably adapted target decoration template, does not necessarily contain pixel-perfect information. Instead, it can contain information describing the control of the corresponding printing or embossing device and / or a transport device that moves the workpiece. For example, the target decoration template can contain information about the target rotational speed of the printing or embossing device and / or the target contact pressure of the printing or embossing device and / or the target transport speed of the transport device in order to set a desired relative movement between the printing or embossing device and the workpiece surface.

[0085] Preferably, step S5 comprises creating at least one control parameter used to control the application process. The target decorative template adapted in step S5 is used either directly to control the application device by allowing the application device to process the information it contains directly. In this case, the adapted target decorative template already contains the at least one control parameter. Alternatively, a further step may be provided in which control parameters readable by the application device are created from the adapted target decorative template. This can be the case, particularly with analogous application processes, by, for example, converting the adapted target decorative template into the aforementionedControl parameters such as target rotational speed of the printing or embossing medium and / or target contact pressure of the printing or embossing medium and / or target transport speed of the transport device are converted.

[0086] Preferably, step S1 includes applying the base decoration to the workpiece surface. Similar or identical application methods to those described for the additional decoration are conceivable here. Therefore, reference is made to the description above.

[0087] Preferably, the method comprises a further step in which the workpiece undergoes post-processing. This post-processing can, in particular, include curing the materials applied to the workpiece, especially the base decoration and any additional decoration. This curing can specifically involve radiation curing, such as UV curing or electron beam curing. Furthermore, additional steps can be performed, such as coating with a sealing layer to increase the durability of the resulting decorative surface.

[0088] Preferably, the process includes a further step in which the workpiece undergoes an additional processing step before step S6. For example, an intermediate coating can be applied here to create better adhesion conditions for the additional decoration. It can also be provided that marks, edges, and decorative elements of the base decoration are removed before the additional decoration is applied, as these should not be visible on the final product.

[0089] In addition to the method according to the invention, a device for carrying out the method described above is provided. It is clear to those skilled in the art that the device elements mentioned above in the description of the method can also be part of the device described below.

[0090] According to the invention, a device for carrying out the method described above is provided. The device comprises the following elements: a detection device configured to detect a base decoration on a workpiece surface; an application device configured to apply an additional decoration to the workpiece above the base decoration; and a control device configured to control the device and its elements according to the method described above.

[0091] Preferably, the detection device includes a detection means for capturing the base decoration on the workpiece surface. As described above, the detection means can operate without contact, as is the case with a camera or an inductively or capacitively operating detection means. However, it is also possible for the detection means to capture the base decoration by means of contact, as described above.

[0092] Preferably, the detection device includes a detection means for capturing the base decoration on the workpiece surface. As described above, the detection means can operate without contact, as is the case with a camera or an inductively or capacitively operating detection means. However, it is also possible for the detection means to capture the base decoration by means of contact, as described above.

[0093] The at least one control device may, in particular, include a control means configured as an electronic data processing unit. The control means may, in particular, be configured as a computer or control unit. It may also be provided that several control devices are provided, each controlling individual elements of the device. For example, one control device may be configured to control the detection of the base decor and, in particular, to control the detection device, while another control device may be configured to control the application device.

[0094] Preferably, the device further comprises an application device designed to apply the base decoration to the workpiece surface. The application device is positioned upstream of the detection device, allowing the base decoration to be applied to the workpiece before detection takes place. As mentioned above in the description of the method, the application of the base decoration can be digital, analog, or hybrid. Therefore, the application device can be designed accordingly. Furthermore, it can be configured, as described above, to apply the base decoration as a two-dimensional decorative image and / or as a three-dimensional structure.

[0095] Preferably, the device includes as a further element a transport device designed to transport the workpiece to the individual elements of the device. In this way, it is possible to position all elements in a specific sequence along the transport direction of the transport device. In particular, this allows for a device that can process the workpiece in a continuous flow.

[0096] Preferably, the device further comprises a post-processing station designed to rework or finalize the workpiece after the application of the additional decoration. Post-processing can, in particular, include curing the materials applied to the workpiece, especially the base decoration and the additional decoration. For this purpose, the post-processing station can, in particular, include a radiation source, such as a UV radiation source or an electron beam source. Furthermore, the post-processing station can include additional post-processing means, such as a coating agent designed to coat the workpiece with a sealing layer to increase the resistance of the produced decorative surface. Alternatively or additionally, the post-processing station can include cleaning agents and / or material removal agents. Cleaning agents are designed for cleaning the workpiece.Material removal devices are designed to remove material from the workpiece, in particular material from the base decoration and / or the additional decoration. This may include, in particular, a suction device designed to extract material from the workpiece for cleaning or designed to vacuum up material from the workpiece, in particular material from the base decoration and / or the additional decoration. A material removal device may include a brush or other mechanically acting means with which material can be removed from the workpiece. Furthermore, it is possible that the cleaning agent and / or the material removal device may include a blower designed to direct a fluid flow, in particular an air flow, onto the workpiece to carry out the cleaning and / or material removal.

[0097] Preferably, the device includes as a further element an intermediate processing station designed to subject the workpiece to at least one additional processing step before the application of the additional decoration. For this purpose, the intermediate processing station may, for example, include an intermediate coating agent to create better adhesion conditions for the additional decoration. It may also be provided that components of the workpiece are removed by means of the intermediate processing station. This may particularly include marks, edges, and decorative elements of the base decoration before the additional decoration is applied, as these should not be visible on the final product. The intermediate processing station may also be used to clean the workpiece. In this case, the intermediate processing station may include cleaning agents and / or material removal agents as described above in the context of the post-processing station.The intermediate processing station can also be designed to perform curing, partial curing, or intermediate drying of the workpiece or components thereof. For this purpose, the intermediate processing station can, in particular, include a radiation source, such as a UV radiation source or an electron beam source.

[0098] The invention is described in more detail below with reference to the accompanying drawings.

[0099] They show: Figure 1a: Measurement parameters that can be recorded during the acquisition of the base decoration, Figure 1b: Deviations of the base decoration, Figure 2: A device for carrying out the method according to the invention, Figures 3a, 3b: Show exemplary states of a workpiece 1 during the execution of the method according to the invention, Figure 4: An exemplary sequence of the method according to the invention, Figures 5a, 5b: An adjustment of the target additional decoration template.

[0100] Figure 1a This shows measurement parameters that can be acquired when capturing the base decor. This is not to be interpreted as limiting the invention. Instead, it represents one way of implementing the invention, more precisely, the measurement of the base decor, particularly when the base decor is rectangular.

[0101] Shown is an example of a rectangularly framed target base decoration, describing a target state for a base decoration, more precisely, its planar extent on a workpiece surface. It has opposite sides a and b, as well as c and d. Parallel to sides a and b, further segments a1 and a2 are drawn. These are located between sides a and b and can, for example, be arranged between the sides such that sides c and d are each divided into three equidistant sections.

[0102] The actual sides a, b, c, d, as well as the other actual segments a1 and a2 present in the base decoration actually present on the workpiece, are now determined by measuring the base decoration after the base decoration present on the workpiece has been recorded. If the base decoration is bordered by an edge, the sides a, b, c, d and the segments a1 and a2 can be determined by measuring the recorded edge. If no edge is present, markings or decorative elements present and recorded on the base decoration can also be used for the measurement, as explained above by way of example in the general description of the invention. In particular, the four corners of the rectangle as well as the intersections of the segments a1 and a2 with the sides c and d can be defined by markings and / or decorative elements of the base decoration. In the case shown here, the recording of the position of eight markings or...Decorative elements of the actual base decor are required.

[0103] If the actual base decoration on the workpiece is identical to the corresponding target base decoration—that is, if there is no distortion, incorrect positioning, or rotation of the base decoration on the workpiece—then sides a, b, c, d and lengths a1 and a2 of the actual base decoration on the workpiece correspond to those of the target base decoration. An additional decoration can then be applied using the target additional decoration template, which has not undergone any adjustments. If there is no identity between the actual base decoration on the workpiece and the corresponding target base decoration, then deviations from those of the target base decoration will occur on sides a, b, c, d and lengths a1 and a2 of the actual base decoration on the workpiece. An adjustment of the target additional decoration template is then necessary to achieve synchronous application of the additional decoration with the base decoration.

[0104] The segments a1 and a2 can be used, in particular, to identify distortions of the actual base decoration. The length and width of the actual base decoration need not necessarily be uniform. Instead, it is possible that the base decoration has been distorted in such a way that side b is longer than side a. With a uniform or linear distortion of the base decoration, the segments a1 and a2 would increase in width according to their position between sides a and b. If the segments a1 and a2 do not correspond to this linear increase, then a different, i.e., non-linear, distortion of the base decoration can be assumed.

[0105] Examples of such deviations are in Figure 1b shown.

[0106] In views 1.1 to 1.4, the actual base decor is shown using dashed lines, which differ from the target base decor shown using solid lines. The target base decor is rectangular. For clarity, the segments a1 and a2 have not been shown here.

[0107] Figure 1.1 shows a case where side b is shortened compared to the corresponding length of the intended base decoration. Sides c and d, on the other hand, are longer and converge towards side b. They are therefore not parallel as they are in the intended base decoration. The segments a1 and a2 (not shown) are correspondingly shortened. These can, for example, be positioned equidistant between sides a and b, as described above.

[0108] Figure 1.2 shows another case. Here, length c is shorter and length d is longer compared to the target base decor, and therefore side b is no longer parallel to a. The segments a1 and a2 (not shown) are positioned here, for example, so that they divide sides c and d equidistantly. Accordingly, changes in the lengths of segments a1 and a2 may be observed.

[0109] As shown in Figure 1.3, both sides c and d are elongated compared to the target base decoration. In contrast, sides a and b, and thus also the sections a1 and a2 (not shown), remain unchanged. This is a case where an analogous application process can be adapted accordingly by adjusting the target additional decoration template. If the additional decoration is applied parallel to sides c and d between sides a and b, the distortion of the base decoration present here, which is uniform along the contours of sides c and d and essentially corresponds only to an elongation of the base decoration, can be addressed by modifying the control of the analogous printing or embossing agent. Instead of a rolling motion (i.e., the relative speed between the printing or embossing agent and the workpiece surface is zero), a sliding motion (i.e.,(The relative speed between the printing or embossing medium and the workpiece surface is not equal to zero) is set so that the additional decoration experiences a distortion in the direction of elongation during application, so that synchronicity between the base decoration and the additional decoration is restored.

[0110] Finally, view 1.4 shows a widening of side b, while side a has not changed in length. Sides c and d now diverge and are therefore no longer parallel.

[0111] The cases shown here can occur particularly when the base decoration is on a stretchable material, such as a plastic or PVC film, that has been laminated or glued onto the surface of the workpiece. The lamination or gluing process can cause stretching and / or compression, or generally distortion, of the film and thus of the base decoration. Other scenarios are conceivable in addition to those shown here.

[0112] However, other methods for applying the base decoration are also conceivable, in particular printing and structuring processes as described above. The in Figure 1bThe cases shown, and others, can also occur with different application methods for the base decoration. For example, a two-dimensional decorative image applied using analog printing methods can exhibit a corresponding defect due to misalignment of the printing roller or the workpiece. Similar defects can also occur when using digital printing methods, for instance, if printing material is applied in the wrong place. This applies to both two-dimensional and three-dimensional base decorations.

[0113] Figure 2 shows a device for carrying out the method according to the invention.

[0114] A device 10 is shown, which includes a transport device 60 for providing S1 of a workpiece 1, on which a workpiece 1 can be transported to the individual elements of the device 10. The workpiece 1 has a workpiece surface 1a on which a base decoration is located.

[0115] The workpiece surface 1a is fed by the transport device 60 to a detection device 20, which is an element of the device 10. The detection device 20, which has a detection element, detects the base decoration on the workpiece surface 1a according to step S2. The information from the detection, for example in the form of image data, is forwarded to a control device 40, which here is designed as a data processing device, for example as a computer.

[0116] The control device 40 is designed not only to control the individual elements of the device 10, but also to measure S3 of the base decor based on the information from the acquisition by the acquisition device 20.

[0117] The detection device 20 includes a camera with which it can detect the workpiece surface 1a with the base decoration applied to it. Other embodiments of the detection device 20 can be configured, for example, as described above.

[0118] To the right of the detection device 20 is an application device 30, which is enclosed here by a dashed frame. This device is designed to apply an additional decoration above the base decoration to the workpiece 1 according to step S6. In the case shown here, the application device 30 is divided from left to right into a coating station 31, a curing station 32, a structuring station 33, and another curing station 34. The application device 30 shown here serves to apply a three-dimensional additional decoration to the workpiece 1. The additional decoration is applied here by means of a negative structuring process in which depressions are created in a previously applied base layer 1b.

[0119] The coating station 31 applies a base layer 1b to the workpiece 1 using application rollers. This base layer is positioned above the workpiece surface 1a, on which the base decoration is located. The curing station 32 is designed to cure the base layer 1b so that it has a gelled consistency, meaning its flowability has decreased compared to the state immediately after application by the coating station 31. Indentations created in the base layer 1b do not immediately disappear but remain at least until further curing can take place to fix the additional decoration in its shape.

[0120] The workpiece 1 with the gelled base layer 1b is fed to the structuring station 33 after the curing station 32. This station is designed to create depressions in the base layer by means of a structuring agent dispensed in the form of droplets. These droplets displace the base layer 1b, for example, through mechanical impulse, thereby forming the corresponding depressions. The structuring station 33 has a digital printing medium, such as a digital printhead or a digital print bar, for dispensing the droplets.

[0121] The structured base layer 1b is finally fixed in the hardening station 34.

[0122] Both hardening stations 32, 34 can be designed as UV radiation sources that emit UV light onto the base layer 1b to harden it.

[0123] The control device 40 is designed to control the application device 30, or at least the structuring station 33, in order to apply the additional decoration to the workpiece 1.

[0124] To apply the additional decoration, which is matched to the base decoration, the control device 40 activates the application device 30 based on a modified target additional decoration template 200', which is provided as a digital data set. To generate the modified target additional decoration template 200', the control device 40 uses the information about the actual base decoration present, which was obtained by the detection device 20. The control device 40 compares this information with a target base decoration 150, which is also provided as a digital data set.

[0125] The target base decor 150 contains information about how the base decor should appear on workpiece 1. As shown here, this can be actual decor information. In this case, the target base decor 150 is a digital data set according to which the base decor was applied to the workpiece surface 1a. However, it can also contain simplified information about individual base decor elements. Furthermore, the target base decor 150 may contain information about markings and / or an edge of the base decor as described above, or it may contain only this information.

[0126] The control device 40 is designed to detect deviations of the actual base decoration present on the workpiece surface 1a from the target base decoration 150 and to determine a necessary adjustment from these deviations in order to adapt a target additional decoration template assigned to the target base decoration 150 so that it serves as the adapted target additional decoration template 200' for applying the additional decoration, after which the additional decoration can be applied at least partially synchronously with the base decoration on the workpiece 1. One way in which the adaptation of a target additional decoration template can be carried out is described by means of the Figures 5a and 5b Explained further below.

[0127] Providing S4 and adapting S5 the target additional decoration template can be done by the control device 40.

[0128] The adapted target additional decoration template 200' contains the information, for example as a digital data set, that must be processed by the application device 30, and in particular by the structuring station 33, in order to apply the additional decoration to the workpiece 1. By adapting the target additional decoration template to the adapted target additional decoration template 200', feedback on the actual conditions of the base decoration (actual base decoration) on the workpiece surface 1a is now available, and thus the target additional decoration template can be adapted accordingly to the adapted target additional decoration template 200'.If the base decoration, particularly with regard to orientation, proportion, and / or position, does not correspond to the target base decoration on the workpiece surface 1a, the target additional decoration template can also be adjusted so that it is adapted to the base decoration actually present on the workpiece surface 1a, particularly with regard to orientation, proportion, and / or position. In this way, a target additional decoration template 200' that is adapted as synchronously as possible is used for applying the additional decoration, and which is not based on a target base decoration, but rather on the base decoration actually present on the workpiece 1. The application of the additional decoration according to the adapted target additional decoration template 200' is then carried out by the control device 40, which activates the application device 30 according to the adapted target additional decoration template 200'.

[0129] A post-processing station 70 is optionally provided downstream of the application device 30. This station can include cleaning agents that act either contact-based or non-contact. For example, the post-processing station 70 may have a brush or other mechanical contact element to remove material from the workpiece 1. It is also possible for cleaning or post-processing to be carried out by means of a fluid flow. Furthermore, the post-processing station 70 may be configured to apply a final coating to the workpiece to protect the applied decoration, including both the base decoration and any additional decoration.

[0130] The application device 30 can also be configured in a further embodiment to operate according to an analog or a hybrid structuring process. It can also apply a two-dimensional additional decoration instead of a three-dimensional structure. This is used, for example, in the production of high-quality brochures or posters where a color-printed photograph (base decoration) is to be given a different gloss level in selected areas with a high-gloss varnish (additional decoration).

[0131] In the example above, the base decoration can be a two-dimensional design, as is the case with a decorative image. In particular, a wood surface can be represented by the base decoration. The additional decoration can then be a three-dimensional design applied over the base decoration and coordinated with the base decoration actually present on workpiece 1 in such a way that it is applied at least partially synchronously. The additional decoration is designed so that the base decoration can be seen through it. It can therefore be partially or completely transparent.

[0132] Besides this configuration of base and supplementary decoration, other configurations of both are possible. For example, both decorations can be two-dimensional or three-dimensional. If both decorations are two-dimensional, this involves, for instance, applying a decorative image (the supplementary decoration) over an existing decorative image (the base decoration) on the workpiece. If both decorations are three-dimensional, applying the supplementary decoration (a three-dimensional structure) over the base decoration is equivalent to adding the supplementary decoration to the base decoration. Furthermore, it is possible for the base decoration to be three-dimensional, with the supplementary decoration applied as a two-dimensional element, such as a coloring of the base decoration, over the base decoration.

[0133] In the example shown here, the application device 30 is designed to apply a negative texture as an additional decoration to the workpiece 1. However, this is not to be understood as a limitation. Rather, other application devices are also conceivable, which can be provided in combination with or instead of the application device 30 shown here. The prerequisite for this is that the corresponding application device 30 is designed to process the information of the desired additional decoration template so that a corresponding additional decoration can be applied.

[0134] The Figures 3a and 3b The figures show exemplary states of a workpiece 1 during the execution of the method according to the invention.

[0135] Figure 3aFigure 1 shows workpiece 1 before the additional decoration was applied. Workpiece 1 has a base body 1c, which is designed, for example, as a plate or panel. The top surface of the base body 1c is coated with a primer or adhesion promoter 1d to create adhesion between the base body 1c and a PVC film 1e applied over it. The PVC film 1e is printed on its top surface with a base decoration 2 and coated with a transparent PVC film 1f, through which the base decoration 2 is visible from above. The surface of the PVC film 1e now forms the workpiece surface 1a on which the base decoration 2 is located.

[0136] Figure 3b Figure 1 shows the application of an additional decoration 3 as a three-dimensional structure above the base decoration 2. For this purpose, a base layer 1b was applied to the PVC film 1f. This base layer 1b is then applied by means of droplets 4, which are applied by an application device 30, as described in Figure 2. Figure 2As shown, the structure is achieved by the droplets creating 4 indentations in the base layer. Based on the adapted target additional decoration template, which is adapted to the base decoration 2 on the workpiece surface 1a, the additional decoration 3 is now created in such a way that any mismatch between base decoration 2 and additional decoration 3 is minimized.

[0137] Figure 4 Figure 1 shows an exemplary sequence of the method according to the invention. Steps S1 to S6 are carried out sequentially.

[0138] According to step S1, a workpiece is provided that has a surface on which a base decoration is applied. The base decoration can be two-dimensional as a decorative image or three-dimensional as a structure, as described above.

[0139] The base decoration on the workpiece is now captured in step S2 using a scanning device. This device may include a camera, particularly for optically capturing the base decoration. Other configurations of the scanning device are also possible, as described above. In particular, the scanning may include capturing marks, decorative elements, and / or an edge of the base decoration as described above, or it may focus exclusively on capturing marks, decorative elements, and / or an edge of the base decoration.

[0140] After being captured in step S3, the base decor is measured based on the captured data or information about it. This means that information about the orientation, proportion, and / or position of the base decor is determined. As described above, this can be done, for example, using the captured marks, decorative elements, and / or an edge of the base decor. Alternatively, the base decor can be measured as a whole. In this way, the actual base decor present on the workpiece is described in such a way that a target additional decor template can be determined, which is then provided in step S4.

[0141] The target additional decoration template describes the additional decoration that is to be applied over the base decoration if the base decoration does not deviate from a target base decoration to which the additional decoration is matched. The target additional decoration template can be designed in various ways. In particular, it can exist as a digital data set, according to which a digitally operating application device can apply the additional decoration.

[0142] Based on the captured base decor already present on the workpiece surface, the target additional decor template is adjusted according to step S5 to match the actual base decor on the workpiece surface. This means that the original target additional decor template is not used to apply the additional decor according to step S6. Instead, an adjusted target additional decor template is used, now adapted to the actual base decor present on the workpiece.

[0143] This minimizes any mismatch between the base decoration and the additional decoration on the workpiece. The adjustment itself can be carried out as described above.

[0144] It is clear to a person skilled in the art that steps S1 to S6 do not necessarily have to be performed in this order. Instead, for example, steps S2 and S3 may be performed simultaneously or by the same device, namely the detection device. The provision of the target additional decoration template may also occur before steps S1 to S3 or between individual steps. Furthermore, steps S5 and S6 may also be performed simultaneously, so that the target additional decoration template is adjusted to include precisely the information required for application according to S6. In particular, steps S4 to S6 may be performed simultaneously.The information required for applying the additional decoration is provided from the target additional decoration template according to step S4. This template is then adapted according to step S5, and subsequently, the additional decoration is applied according to this adapted target additional decoration template. For example, this can be done for steps S5 and S6, or S4, S5, and S6, by providing a pixel-based target additional decoration template. In step S4, one or more pixel rows are provided perpendicular to the workpiece feed direction. These rows are then adapted according to step S5, and the decoration is subsequently applied according to step S6 based on the adapted pixel rows. This process is repeated until the additional decoration has been applied according to the entire adapted target additional decoration template.

[0145] Figure 5a and 5b show how an adjustment of a target additional decoration template can be made.

[0146] View 5.1 shows a workpiece 1 in a top view. Workpiece 1 is rectangular. View 5.2 shows a target additional decor template 200, which has not been further modified. The target additional decor template 200 is visualized as an additional decor, in this case a wood decor. The target additional decor template 200 is designed to correspond to a target base decor (not shown) or to a base decor (not shown) that was applied to workpiece 1 without deviation from the target base decor. An additional decor that would be applied to workpiece 1 according to the target additional decor template 200 would then be synchronous with such a base decor on workpiece 1, which corresponds to the target base decor and shows no deviations from it.

[0147] However, the actual base decoration 2 present on workpiece 1 deviates from the target base decoration, as can be seen in Figure 5.3. Here, an actual base decoration 2 is shown. The causes of such deviations arise from errors or inaccuracies in the application process of the base decoration 2, as explained above. If the base decoration 2 is applied to workpiece 1 using an analogous process, an error can, for example, be introduced into the base decoration 2 by a sliding application roller. If the base decoration 2 is laminated using film, an error can be introduced into the base decoration 2 by stretching, compression, or similar distortion of the film. In the present example, the proportions of the base decoration 2 are altered, in particular, such that the right edge of the base decoration 2 is slanted. Figure 5.Figure 4 shows the actual position of the base decoration 2 on the workpiece 1 and another error that occurred during the application of the base decoration 2 to the workpiece 1. Here, the base decoration 2 is rotated to the right. This means that the orientation of the base decoration 2 deviates from that of the intended base decoration.

[0148] Figure 5.5 illustrates that applying the additional decoration 2 according to the additional decoration template 200 without adjusting it will result in a mismatch. The structures of base decoration 2 and additional decoration 3 do not align. Therefore, the target additional decoration template 200 must be adjusted to the actual base decoration 2.

[0149] How such an adjustment can be made is shown Figure 5b .

[0150] View 5.6 shows workpiece 1 from View 5.4, where the base decoration 2 is distorted and rotated on the surface. Key points of the base decoration 2 are marked with black markings. These key points may be decorative elements of the base decoration 2. However, they may also be other key points, such as specially applied marks or the edge of the base decoration 2. These key points function as synchronization elements 2a and lead to a simplified description of the base decoration 2. That is, based on the position of the synchronization elements 2a on workpiece 1 and their relationship to each other, information about the orientation, proportion, and / or position of the base decoration 2 on workpiece 1 can be obtained.In the present example, the synchronization elements 2a should actually be arranged in a regular 4x4 matrix, in which adjacent synchronization elements 2a are equidistant and aligned with each other in a vertical and horizontal direction in the drawing plane. This is clearly not the case here. Instead, the 4x4 matrix is ​​distorted due to errors in the application of the base decor 2. The synchronization elements 2a are no longer aligned and are no longer equidistant from each other.

[0151] View 5.7 shows the visualized additional decor template 200 before its adaptation. The additional decor template 200 has adaptation elements 200a, which are marked here with circles. These elements would be synchronized with the synchronization elements 2a of the base decor 2 if there were no errors in the base decor 2. View 5.8 shows the corresponding deviation between the adaptation elements 200a (circles) of the unadapted target additional decor template 200 and the synchronization elements 2a of the base decor 2 (black markings).

[0152] The target additional decor template 200 must now be adapted to the deviations of the base decor 2. For this purpose, displacement vectors are calculated, which result for each individual pair of adaptation element 200a and synchronization element 2a. A displacement vector thus represents the positional deviation of a synchronization element 2a relative to the corresponding adaptation element 200a.

[0153] Based on the displacement vectors, the additional decorative template 200 is distorted, rotated, and adjusted in position using a mathematical model and then fed as a digital data set to an application device designed for applying the additional decorative element. In particular, a vector field can be determined from the displacement vectors, according to which even sections of the additional decorative template 200 that do not correspond to one of the adjustment elements 200a can be adjusted. Thus, the entire additional decorative template 200 is adjusted so that it is aligned with the actual base decorative element 2. The transfer of the positions of the synchronization elements 2a to the adjustment elements 200a is shown in Figure 5.9. The result is an adjusted target additional decorative template.

[0154] The invention will now be explained using specific exemplary embodiments. In doing so, reference will be made to... Figure 2Reference has been made to this. It is clear to an expert that individual characteristics can be extracted separately and combined with other characteristics mentioned above. Example 1:

[0155] A workpiece 1 in the form of a 5.5 mm thick PVC sheet, filled with a calcium binder, is thermally laminated (not shown) with a PVC film printed with a base design using a solvent-based gravure printing process. For this purpose, the PVC sheet is heated to approximately 170 °C in a heated calender and laminated with the printed PVC film. In an alternative embodiment, a transparent, unprinted PVC film is placed over the aforementioned printed PVC film, and both PVC films are thermally laminated onto the PVC sheet in a heated calender. The printed PVC film has a thickness of 0.2 to 1.5 mm, or in an alternative embodiment, a thickness of 0.3 to 0.6 mm. The transparent, unprinted PVC film has a thickness of 0.2 to 1.2 mm, or in an alternative embodiment, a thickness of 0.3 to 0.6 mm.The workpiece 1 produced in this way is fed to the detection device 20 via a transport device 60. After optical and / or non-optical detection and measurement, the workpiece 1 is fed by the transport device 60 to an application device 30. Here, a coating station 31 applies one or more coats of a UV-curing acrylic lacquer as a base coat 1b. In a subsequent curing station 32, this acrylic lacquer is partially cured with a corresponding dose of UV radiation, whereby the wavelengths of the radiation used have a maximum at 395 nm. The curing is not complete (the double bonds formed during the curing and polymerization of an acrylic lacquer are not 100% converted).In a subsequent structuring station 33, a UV-absorbing agent is applied in droplet form to the base layer 1b via digital printheads, so that the base layer 1b is shielded from UV radiation by the agent in the areas where it was applied. The treated workpiece 1 is then transferred to a curing station 34, which uses correspondingly higher UV intensities than curing station 32 to completely cure the base layer 1b in all areas not shielded by the agent. The treated workpiece 1 is then transferred to a post-processing station 70. Here, the parts of the base layer 1b that were covered by the agent and therefore not yet fully cured after curing station 34 are removed. A brush, for example, can be used for this purpose.In the example described here, the application of the droplets from the structuring station 33 is digitally controlled. For this purpose, a customized structure file, the customized target additional decoration template 200', is used. This template was generated electronically in the control device 40 from the information of the detection device 20 and the previously existing target base decoration 150, which describes a target state of the base decoration. The target base decoration 150 can, for example, contain information about the target base decoration as a whole, or about marks, edges, and / or individual decorative elements, which then serve to adapt the target additional decoration template to the customized target additional decoration template 200'.

[0156] According to one aspect of the invention, the base decoration is applied to the workpiece surface beforehand using digital, analog, or hybrid application methods. The desired base decoration can serve as a template for this purpose.

[0157] According to one aspect of the invention, at least two decorative elements or marks in the base decor are detected by measurement and used to adapt the target additional decor template.

[0158] According to a further aspect of the invention, the measurement is carried out without including the target base decor. In particular, it can be provided that a target base decor does not exist. The adapted target additional decor template 200' is then generated exclusively from the data or information of the measurement and the target additional decor template. This can be done, for example, by the adaptation of adaptation elements and synchronization elements described above. Example 2:

[0159] A titanium dioxide-filled decorative paper weighing 55 to 80 g / m² is printed with a base decor, for example an oak decor, using an aqueous ink in a gravure printing process. The printing press is equipped with its printing cylinders according to a specified base decor. During the printing and subsequent drying process, the dimensions of the paper change, e.g., in the longitudinal and / or transverse direction. The paper is then bonded to a 6 mm thick HDF board using a two-component urea resin / hardener adhesive. Subsequently, the bonded and printed paper is coated in one or more steps with a melamine resin mixture, dried in one or more drying processes to a residual moisture content of less than 30%, preferably less than 15%, and pressed in a hot press at 35 bar pressure and 210 °C.The resulting workpiece 1 is fed to the detection device 20 for subsequent coating with the additional decoration in the application device 30. For this purpose, a UV-curing acrylic lacquer is applied to the surface via the coating station 31. This lacquer is then structured (in particular, negative structuring) by the structuring station 33 without any further intermediate steps using digital droplets introduced into the still-liquid lacquer layer at a speed of 3-8 m / s. The lacquer layer is then cured in station 34. The structuring station 33 is controlled here, as described in embodiment 1, by a control device 40. This device generates an adapted target additional decoration template 200' from the results of the detection device 20 and stored data on the target base decoration 150 in order to control the structuring station 33.The result is a melamine-coated furniture or floor panel that has a lacquered structure (additional decor) on its surface to match the printed oak decor. Reference symbol list

[0160] 1 Workpiece 1a Workpiece surface 1b Base layer 1c Base body 1d Primer or adhesion promoter 1e PVC film 2 Base decor or actual base decor 2a Synchronization element 3 Additional decor 3c Decor element 4 Droplet 10 Device 20 Detection device 30 Application device 31 Coating station 32 Curing station 33 Structuring station 34 Curing station 40 Control device 60 Transport device 70 Post-processing station 150 Target base decor 200 Target additional decor template 200'Adapted target additional decor template 200a Adaptation element a Side a 1 Section a 2 Section b Side c Side d Side

Claims

1. Method for producing a decorative surface on a workpiece (1) comprising the following steps: - step (S1): providing a workpiece (1) having a workpiece surface (1a) on which a base decor (2) is present; - step (S2): detecting the base decor (2) on the workpiece surface (1a) using a detection device (20); - step (S3): measuring the detected base decor (2); - step (S4): providing a nominal supplementary decor template (200) for a supplementary decor (3), the nominal supplementary decor template (200) being configured synchronously with a nominal base decor (150); - step (S5): adapting the nominal supplementary decor template (200) on the basis of the measured base decor, so that an adapted nominal supplementary decor template (200') is obtained, according to which the supplementary decor (3) can be applied at least partially in synchronism with the base decor (2); - step (S6): application of the supplementary decor (3) onto the workpiece (1) above the base decor (2) in accordance with the adapted nominal supplementary decor template (200') using an application device (30), wherein in step (S3), information about the nominal base decor (150) is provided and a deviation of the base decor (2) from the nominal base decor (150) is determined by comparing the detected base decor (2) with the nominal base decor (150).

2. The method according to claim 1, wherein the detection of the base decor (2) in step (S2) is carried out in a contactless manner, in particular optically, capacitively, inductively and / or by some other means.

3. The method according to any one of the preceding claims, wherein in step (S2), the detection of the base decor (2) comprises a detection of marks (2a) of the base decor (2), and / or wherein in step (S2), the detection of the base decor (2) comprises a detection of at least one edge (2b) of the base decor, and / or wherein in step (S2), the detection of the base decor (2) comprises a detection of at least one decor element (2c) of the base decor (2).

4. The method according to any one of the preceding claims, wherein in step (S3), information about the orientation, proportion and / or position of the base decor (2) on the workpiece surface (1a) is determined.

5. The method according to any one of the preceding claims, wherein the information about the nominal base decor (200) is provided as a digital dataset.

6. The method according to any one of the preceding claims, wherein the result from the measurement according to step (S3) and / or the nominal supplementary decor template is provided as a digital dataset.

7. The method according to any one of the preceding claims, wherein step (S5) comprises adjusting at least one of the orientation, proportion and / or position of the nominal supplementary decor template, and / or shifting adjustment elements of the nominal supplementary decor template in accordance with the base decor (2) in order to adapt the nominal supplementary decor template to the base decor (2).

8. The method according to any one of the preceding claims, wherein the base decor (2) comprises a two-dimensional decor image and / or a three-dimensional structure, or wherein the base decor (2) consists of a two-dimensional decor image and / or a three-dimensional structure, and / or wherein the supplementary decor (3) comprises a two-dimensional decor image and / or a three-dimensional structure, or wherein the supplementary decor (3) consists of a two-dimensional decor image and / or a three-dimensional structure.

9. The method according to any one of the preceding claims, wherein step (S6) comprises that the supplementary decor (3) is applied by means of a digital application method, an analog application method or a hybrid application method.

10. The method according to claim 9, wherein the adapted nominal supplementary decor template is used to control the application method used and is preferably present as a digital dataset.

11. The method according to any one of the claims 8 to 10, wherein step (S5) comprises generating at least one control parameter that is used to control the application method used.

12. The method according to any one of the preceding claims, wherein step (S1) comprises applying the base decor (2) onto the workpiece surface (1a), and / or the method comprises a further step (S7) in which a post-processing of the workpiece (1) is carried out, and / or the method comprises a further step in which the workpiece (1) is subjected to a further processing step before step (S6).

13. Device (10) for carrying out the method according to any one of the preceding claims, having the following elements: - a detection device (20) configured to detect a base decor (2) on a workpiece surface (1); - an application device (30) configured to apply a supplementary decor (3) onto the workpiece (1) above the base decor (2); and - a control device (40) configured to control the device (10) and its elements in accordance with the method according to any one of the preceding claims.

14. The device (10) according to claim 13, further comprising the following elements: - an application device configured to apply the base decor (2) onto the workpiece surface (1a); and / or - a transport device (60) configured to transport the workpiece (1) to the individual elements of the device (10); and / or - a post-processing station (70) configured to post-process or finalize the workpiece (1) after the supplementary decor (3) has been applied; and / or - an intermediate processing station configured to subject the workpiece (1) to at least one further processing step before the supplementary decor (3) is applied.

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