METHOD FOR PRINTING A DECOR ONTO A SUPPORT MATERIAL

Description

[0001] The invention relates to a method for digitally printing a design onto a substrate material with at least one set of defined printing parameters. The method comprises the steps i. Providing an analog decor; ii. Generating and storing at least one digital image in the form of digital decor raw data in the RGB color space from the analog decor; iii. Digitally processing at least a portion of the digital decor raw data in the RGB color space and generating processed digital decor raw data; iv. Providing at least one set of printing parameters; v. Transferring the processed digital decor raw data and the at least one set of printing parameters to color management or RIP software and calculating color space-profiled production data for the at least one set of printing parameters from the processed digital decor raw data; vi. Calculating separation data from the color space-profiled production data calculated for the at least one set of printing parameters; vii.Output of a digital image of the analog decor with the calculated separation data by a digital printer onto a substrate, wherein the digital printer includes at least one set of printing parameters for which the color space-profiled production data were calculated.

[0002] For the production of decorative elements, especially for floor panels, furniture components, or worktops, gravure printing cylinders are typically used. A printed decorative element is generally created from a digitized analog design, which is based on a real material such as wood. The digital data of the analog design, i.e., its digital images, are usually generated by scanning or digital photography. These images are captured and stored in the RGB color space by the red / green / blue sensors in digital cameras or scanners. The RGB color space is an additive color space that reproduces color perception by additively mixing the primary colors red, green, and blue. To transfer this digital RGB decorative element data set to a set of printing cylinders with multiple individual colors, the data for the individual colors to be printed must be separated.

[0003] Digital printing is increasingly becoming established alongside the historically rooted gravure printing process in decorative printing. In digital printing, the print design is transferred directly from a computer to a digital printer, such as a laser or inkjet printer. Therefore, digital printing eliminates the need for static printing plates, thus removing limitations on the length and width of the print data. Digital printing therefore offers a high degree of flexibility and variability with regard to print motifs and imposes no restrictions on the repeat pattern. In printing, a repeat pattern refers to a constantly recurring, identical print design.

[0004] One of the best-known color models is the CMYK color model, which uses the primary colors cyan, magenta, yellow, and black for printing. The CMYK color model is a subtractive color model, with the abbreviation CMYK standing for the three color components cyan, magenta, yellow, and the black component (key) representing the color depth. This color system allows for the representation of a color space (gamut) that meets the requirements of many different fields. If a digital printer uses the CMYK color model, it will have four color channels: one for cyan, one for magenta, one for yellow, and one for key.

[0005] According to current technological standards, the digital data is color space profiled. This involves defining the printing parameters relevant for printing, such as... Type of printing system (including printing speed, printhead characteristics, etc.); color model to be used for printing (e.g., 4-color channel printing system, 5-color channel printing system, use of spot colors, etc.); temperature; humidity; type / batch of printing ink; type / batch of substrate to be printed; substrate pretreatment (e.g., by priming); taken into account.

[0006] The printing parameters determine the color space that can be reproduced in print. The color space describes the entirety of colors that can be represented with the given printer parameters. In principle, the color space of color space-profiled production data—that is, the digital data after color space profiling—is smaller than the RGB color space in which the digital data of the analog decor resides, because the color space is limited by the printing parameters.

[0007] The type of printing ink alters the appearance of the printed colors, for example, due to the pigments it contains. Furthermore, even different batches of the same printing ink can exhibit variations in appearance. The same applies to the substrate. With otherwise identical printing parameters, a print on a wood-based panel will look different than one on glossy paper. Even when printing on paper, the appearance of the printed colors depends on the paper used, such as whether it has a white or yellowish / brownish tint. Additionally, papers from different manufacturers can differ in their base color. The substrate can also be pre-treated in various ways, for example, by priming.Priming, in turn, changes the background during printing and thus the color effect of the print.

[0008] The choice of printing system alone influences the color gamut in which printing is possible, as different printing systems have, among other things, different printing speeds and / or printhead settings, which in turn affect the color gamut. Furthermore, different printers use different color models for printing.

[0009] Climatic conditions during printing also influence the color space; for example, the ink dries at different rates depending on temperature and humidity.

[0010] The color space-profiled production data for different printing parameters therefore differ from each other and can represent color spaces of varying sizes depending on the printing parameters.

[0011] From the color space-profiled production data, separation data is calculated for the digital printer used for printing. Typically, printing companies use separated print data for digital printing, similar to how it is used for gravure printing. For use in digital printing, the data of a digital image is converted into a format that can be processed by a digital printer using RIP (raster imaging process) software. The RIP software separates the color information contained in the digital image into, among other things, the color channels that are part of the color model of the digital printer to be used for printing. The digital print output is then carried out by the digital printer using the corresponding color model. Separation data can be calculated, for example, using RIP software, color management software, or software integrated into the printer.

[0012] The separation data, like the profiled production data, is therefore dependent on the printing parameters. In particular, the separation data for printing a design will differ on different printing systems. Here, "printing systems" refers to digital printers, either alone or in a system with other equipment, such as devices for priming and / or transporting substrates.

[0013] Currently, separation data is typically calculated from color space-profiled production data for printing under defined printing parameters. This separation data is then digitally processed to, for example, make color adjustments to the design or retouching. This involves editing and modifying the color information contained in the color channels.

[0014] The separation data available for one set of printing parameters cannot simply be applied to other printing parameters for the reasons already described. In particular, the separation data cannot simply be used for a different printing system. For each changed printing parameter, it is necessary to calculate new color space-profiled production data and thus new separation data. This separation data then needs to be digitally processed to implement desired retouching, such as color adjustments to the decor.

[0015] EP 3 470 972 A1 relates to a method for the multiple use of digital print data to produce high-quality optical and / or tactile printed decorations on a substrate. In this method, separation data of a digital print motif is created, whereby the data of the individual color channels can then be processed individually to retouch the digital print motif.

[0016] However, the current state of the art has numerous disadvantages. Manually separating individual colors before printing with a defined set of printing parameters is very time-consuming in the production process and therefore increases production costs. While the digital data of the analog decor is available in the extensive RGB color space after its creation, the color space of the decor after the calculation of the color space-profiled production data and its separation is limited to colors and / or spot colors of the color model used in printing. The color space-profiled production data, as well as the separation data generated by the separation process, cover a significantly smaller color space than the original digital data of the analog decor in the RGB color space. In particular, separation data for a second printing press cannot be derived from existing separation data for a first printing press.In this case, a reduction in the quality of the printed image would generally have to be accepted.

[0017] For example, if separation data exists for printing with a 4-color system, it cannot be used to calculate separation data for printing on a 5-color system. In this case, data with less information content (for 4 color channels) would have to be used to generate data with more information content (for 5 color channels). This makes it impossible to guarantee a consistently high printing quality standard.

[0018] The invention is therefore based on the objective of providing a method for the digital printing of decorations which can be carried out as flexibly as possible with different printing parameters, in particular different printing systems, and thereby eliminates the disadvantages of the methods known from the prior art.

[0019] For this purpose, the invention provides a method according to claim 1. Detailed description

[0020] According to the inventive method, an analogous decor is provided. In principle, any material that exists in reality and whose appearance is suitable as a decor can serve as an analogous decor. In particular, wood, tile, and stone surfaces can serve as analogous decors. Analogous decors within the meaning of the present invention can also be templates produced using other printing techniques such as intaglio printing, screen printing, or even manual techniques. The decors are particularly popular in the design of laminates used for floor, wall, and / or ceiling coverings.

[0021] In a preferred embodiment, the method according to the invention is preferably used for printing on substrate materials for the production of floor laminates or wall and ceiling cladding elements.

[0022] Subsequently, at least one digital image in the form of digital decor raw data in the RGB color space is generated and stored from the analog decor. In one embodiment of the invention, the at least one digital image, and thus the digital decor raw data of the analog decor, is generated by photographing the analog decor with a digital camera or by scanning the analog decor with a scanner.

[0023] The RGB color space is the largest color space in which digital images can be edited and encompasses all color spaces in which digital printing is possible.

[0024] In one embodiment, multiple digital images of the analog decoration can be generated. For example, the analog decoration can be photographed or scanned from different angles and with different camera or scanner settings. A composite image can then be calculated from the different digital images. Software for scanners is also known in the prior art in which an analog decoration is scanned in three different modes, i.e., under three different conditions (scanner settings, exposure, etc.), and a composite image is subsequently generated. In the method according to the invention, the digital composite image can then be further processed digitally. The digital composite image then represents the raw digital decoration data within the meaning of the invention.

[0025] In one embodiment, special effects such as shading can be created during photography or scanning by using special lighting techniques and varying the position of the camera or scanner over the analog decor.

[0026] According to the method, at least a portion of the digital decor raw data in the RGB color space is digitally processed. During the digital processing of at least a portion of the digital decor raw data, at least a portion of the decor raw data can be retouched. According to the invention, this results in processed digital decor raw data. The processed digital decor raw data, according to the invention, still resides in the RGB color space.

[0027] In one embodiment of the present invention, at least a portion of the digital decor raw data is processed using Adobe Photoshop software. In principle, however, any image editing or graphics editing program that allows the processing, and in particular retouching, of digital image data in the RGB color space is suitable for this purpose. The processing of the digital decor raw data can, for example, be carried out by a user on a PC with suitable software, such as Adobe Photoshop.

[0028] Retouching refers to the subsequent image editing of the digital raw data of a photographed or scanned analog decoration. This can involve... one or more color tones are changed; and / or the brightness is changed; and / or the saturation is changed; and / or the contrast is changed; and / or the sharpness is changed.

[0029] Retouching allows for the modification of the appearance of the digital image, which is defined by the raw digital decor data. The following editing steps always refer to altering the appearance of the digital image as described by the raw digital decor data. This involves editing the raw digital decor data.

[0030] This allows, for example, the correction of errors in the digital image. Furthermore, dust present on the analog decor during digitization can be removed as a visual feature from the digital image and thus from the raw digital decor data. With wood decors, for instance, knots can be removed, added, and / or modified, e.g., their size. Additionally, pattern repeats can be created. In one embodiment, decors intended for planks are processed in such a way that the plank division is no longer visible in the digital image. This has the advantage that, after digital printing in the repeat pattern, planks of any width can be cut from the printed substrate.

[0031] The sharpness of the digital image, or of specific areas within it, can be adjusted. Areas can be made sharper or blurrier. Furthermore, highlights and midtones can be adjusted separately in terms of color and saturation.

[0032] Retouching allows you to emphasize or subtly highlight structures in the digital image of the analog decor by, for example, changing the color in those areas. This way, pores in wood textures, knots, or similar patterns in decors can be emphasized or minimized. Adobe Photoshop, in particular, offers the option of working with multiplication layers. Using this function, one decor layer can be copied within the software and placed above another. The upper decor layer can be made transparent, which advantageously makes the underlying decor layer appear more pronounced.

[0033] During retouching, the color scheme can also be altered. For example, different color areas can be created within a monochromatic design, giving the entire digital image of the analog design more dynamism. Conversely, even in particularly vibrant digital images of an analog design, colors can be reduced or adjusted to give the digital image a calmer appearance.

[0034] Furthermore, it is possible to perform geometric operations such as rotations, reflections, or even a regrouping of certain parts of the digital image.

[0035] The digital raw data for the decor can thus be optimally adapted to customer requirements. Advantageously, this processing is carried out in the largest possible available color space, namely the RGB color space. This ensures that the maximum amount of data is available for processing.

[0036] In one embodiment of the method according to the invention, not only a portion of the raw decorative data is processed, but all of the raw decorative data. This makes it possible to perform retouching across the entire digital image or only on selected areas of the digital image.

[0037] By processing the raw decor data, a processed digital image of the analog decor is created, the appearance (optical impression) of which is changed in comparison to the unprocessed digital image of the analog decor as it was created in process step ii.

[0038] According to the invention, at least one set of pressure parameters is provided. According to the invention, pressure parameters are selected from the group comprising: Type of printing system (including printing speed, printhead characteristics, etc.); color model to be used for printing (e.g., 4-color channel printing system, 5-color channel printing system, use of spot colors, etc.); temperature; humidity; type / batch of printing ink; type / batch of the substrate to be printed; pretreatment of the substrate (e.g., by priming).

[0039] The properties of the pressure parameters are part of the prior art and have already been described. In this case, a set refers to a collection of pressure parameters, wherein exactly one defined value or quantity is provided for each pressure parameter. In one embodiment of the invention, a set of pressure parameters comprises all of the aforementioned pressure parameters or a selection thereof. In one embodiment of the present invention, several sets of pressure parameters are provided. In principle, any number of sets of pressure parameters can be provided. In one embodiment, 2 to 10, preferably 2 to 6, and particularly preferably 2 to 4 sets of pressure parameters are provided.

[0040] The processed digital decor raw data and at least one set of printing parameters are transferred to a color management or RIP software, and color space-profiled production data for the at least one set of printing parameters is calculated from the processed digital decor raw data.

[0041] As previously described, printing systems in this context refer to digital printers, either alone or as part of a system with other equipment, such as devices for priming and / or transporting substrates. The printing parameters, therefore, determine, among other things, which digital printer should be used. Different digital printers generally have different printing characteristics. In this step, a color space adjustment is performed, whereby the color space-profiled production data is then no longer in the RGB color space, but in a smaller, restricted color space. When calculating the color space-profiled production data, the printing parameters take into account the color model used by the digital printer intended for printing.In one embodiment of the present invention, the color space-profiled production data are calculated in a color model selected from the group comprising CMYK, CRYK, 1-color, 5-color, 6-color, 7-color, or even 8-color models. The color models may also include spot colors.

[0042] The color space available for printing is further influenced by the other printing parameters mentioned above. This is known to those skilled in the art and has already been explained. The influence of the printing parameters on the color space is taken into account by calculating the color space-profiled production data. In this process step, the digital data is therefore cropped to the color space used in printing with a digital printer under defined printing parameters.

[0043] If multiple sets of printing parameters are provided, color space-profiled production data is created for each set of printing parameters in one embodiment. According to the invention, the creation or calculation of the color space-profiled production data is based on the processed digital raw decor data. Consequently, the color space-profiled production data is always created starting from the largest possible color space, namely the RGB color space.

[0044] According to the invention, separation data is calculated from the color space-profiled production data calculated for at least one set of printing parameters. The separation data is an assignment of the print data to the individual printheads of the digital printer. This procedure is known to those skilled in the art. In one embodiment, the separation data is calculated from the digital production data by color management, RIP software, or printer-internal software.

[0045] According to the invention, the processed digital image of the analog decor with the calculated separation data is output onto a substrate by a digital printer, wherein the digital printer is comprised of at least one set of printing parameters for which the color space-profiled production data were calculated.

[0046] According to the invention, a digital image of the analog decor, including the separation data, is output by at least one digital printer under the printing parameters defined in the at least one set of printing parameters. These printing parameters correspond to the printing parameters that formed the basis for calculating the color space-profiled production data from which the separation data was calculated. Consequently, the printing parameters used for calculating the color space-profiled production data and the separation data are also used for printing.

[0047] According to the invention, the appearance of the printed decoration on the substrate corresponds to the appearance of the processed digital image as represented by the processed raw decoration data.

[0048] In one embodiment of the invention, in process step vi., separation data is calculated from the color space-profiled production data calculated for each set of printing parameters, and in process step vii., a digital image of the analog decoration, including the calculated separation data, is printed onto a substrate by a digital printer. Each digital printer is associated with the set of printing parameters for which the color space-profiled production data and the respective separation data were calculated. According to the invention, the color space-profiled production data and the separation data calculated therefrom are always calculated for each set of printing parameters, and a digital image is printed using these printing parameters and the calculated separation data.

[0049] Advantageously, this allows for the calculation of color space-profiled production data and, consequently, separation data for printing with different printing parameters and thus for different digital printers. It also allows, for example, the calculation of color space-profiled production data and separation data for printing with the same digital printer and color model, but on different substrates. The starting point in each case is the processed raw decor data, which is in the RGB color space. The color space-profiled production data and the resulting separation data can therefore always be calculated advantageously from the largest possible color space.

[0050] According to the present invention, a graphics department can advantageously perform the retouching of the digital image of the analog decor simply, quickly, and therefore cost-effectively, once in the RGB color space. Unlike prior art, it is not necessary to repeatedly process the separation data. This reduces decor development times by several days to several weeks, representing a significant competitive advantage. Furthermore, it enables faster responses to customer requests.

[0051] Furthermore, the separation data no longer needs to be digitally post-processed, as is common practice in the current state of the art. The digital decor raw data has already been digitally processed and therefore already includes the desired retouching of the digital image of the analog decor. This results in significant time savings and makes the printing process correspondingly more economical.

[0052] In principle, any material suitable for applying a printing medium is suitable as a substrate. The substrate can have a smooth or a rough surface onto which the printing medium is applied. In one embodiment of the invention, the substrate is selected from the group consisting of paper, glass, metal, foils, wood-based materials, plastics and combinations thereof, in particular medium-density fiberboard (MDF), high-density fiberboard (HDF), particleboard, oriented strand board (OSB), plywood and wood-plastic composite (WPC) panels, veneers, lacquer coatings, plastic sheets, fiber-reinforced plastic, hard paper and inorganic substrates.

[0053] In a preferred embodiment, the carrier material has at least one planar shape which can be printed with the printing forms according to the invention.

[0054] Suitable substrate materials can therefore include, for example, laminates, furniture panels, furniture fronts, worktops, door fronts, wallpaper, papers, and glass surfaces. The substrate material can have a smooth or a textured surface.

[0055] In one embodiment of the present invention, at least one primer layer is applied to the side of the substrate to be printed before printing. Particularly when using wood-based panels as the substrate, in one embodiment of the present method, at least one primer layer comprising at least one resin and / or at least one varnish is applied to the side of the wood-based panel to be printed before printing with the digital image, and is subsequently dried and / or cured.

[0056] Furthermore, the primer may contain at least one additive and / or at least one aggregate. Suitable additives are selected from the group containing hardeners, wetting agents (surfactants or mixtures thereof), and release agents. Suitable aggregates are selected from the group containing conductive substances and cellulose. The conductive substances may be selected from the group containing carbon black, carbon fibers, metal powders, and nanoparticles, in particular carbon nanotubes.

[0057] Preferably, the side of the substrate material to be printed, in particular a wood-based panel, is sanded before the primer is applied.

[0058] For priming, an aqueous resin solution and / or a radiation-curable filler can be applied to the side of the substrate to be printed. Suitable primers include aqueous resin solutions such as melamine-formaldehyde resin, urea-formaldehyde resin, or melamine-urea-formaldehyde resin. It is also possible to pre-coat or prime the substrate with 1K / 2K acrylate, UV-cured, and / or ESH filler and then cure this primer layer accordingly.

[0059] Preferably, an aqueous resin solution is used for the pre-coating or priming of the substrate material, in particular a wood-based panel, which is an aqueous resin solution, in particular an aqueous solution of a melamine-formaldehyde resin, urea-formaldehyde resin or melamine-urea-formaldehyde resin.

[0060] The application rate of liquid resin solution for priming can be between 10 and 80 g / m², preferably between 20 and 50 g / m². The solids content of the aqueous resin solution is between 30 and 80%, preferably between 40 and 60%, and particularly preferably between 55%. The liquid resin may additionally contain suitable wetting agents, hardeners, release agents, and defoamers.

[0061] After applying the aqueous resin solution to the substrate for pre-coating or priming, the liquid resin is dried to a moisture content of 10%, preferably 6%, e.g. in a convection oven or near-infrared oven.

[0062] In another embodiment of the present method, the substrate material, in particular a wood-based panel, can be pre-coated or primed with 1K / 2K acrylate and / or ESH filler. A UV-curable filler advantageously consists essentially of UV-curable lacquer components, pigments, reactive diluents, and radical initiators as chain starters.

[0063] The application rate of the leveling compound can be 50 to 150 g / m², preferably 50 to 100 g / m². These quantities refer to a 100% leveling compound.

[0064] It is also possible that the filler used for priming is pigmented, which can vary or improve the printing result.

[0065] Particularly preferred according to the invention is the pre-coating of the substrate material with a transparent primer.

[0066] In a further embodiment of the present method, at least one layer of a pigmented primer, preferably water-based, is applied to the side of the substrate to be printed before printing on at least one side of the substrate, in particular a wood-based panel. The pigmented primer can be applied either directly to the untreated surface of the substrate or to the previous, preferably transparent, primer.

[0067] The water-based pigmented primer can also be applied in more than one layer (e.g., 3 to 10 layers, preferably 5 to 8 layers, particularly preferably 7 layers), wherein after each layer application the pigmented primer is dried, for example, in a convection dryer or a near-infrared dryer. The water-based pigmented primer preferably contains at least one pigment of a light color, particularly preferably at least one white pigment.

[0068] White pigments are achromatic inorganic pigments with a high refractive index (greater than 1.8), primarily used to produce optical whiteness in coatings or as fillers in, for example, plastics. White pigments according to the invention can be selected from the group consisting of titanium dioxide, lithopone, barium sulfate, zinc oxide, zinc sulfide, and calcium sulfate. Lithopone is a white pigment containing barium sulfate and zinc sulfide. According to the invention, titanium dioxide is preferably used as the white pigment in the water-based pigmented primer because titanium dioxide has the highest refractive index and thus the highest opacity among known white pigments.

[0069] The substrate can therefore be primed before printing, and after printing, one or more protective layers, preferably one, two, or three, can optionally be applied. The minimum protective layer comprises abrasion-resistant particles, natural fibers, synthetic fibers, and / or other additives, with resins such as melamine-formaldehyde resin, urea-formaldehyde resin, acrylate resins, and polyurethane resins being suitable binders.

[0070] The abrasion-resistant particles are preferably selected from the group consisting of aluminum oxides, corundum, boron carbides, silicon dioxides, silicon carbides, silanized corundum particles, and glass beads. Applying abrasion-resistant particles and / or glass beads increases the wear resistance of a substrate material with a decorative and optionally textured finish. Natural and / or synthetic fibers are used, in particular fibers selected from the group consisting of wood fibers, cellulose fibers, wool fibers, hemp fibers, and organic or inorganic polymer fibers.

[0071] Conductive substances, flame retardants, luminescent materials, and metals can be added as additives. The conductive substances can be selected from the group containing carbon black, carbon fibers, metal powders, and nanoparticles, particularly carbon nanotubes. Combinations of these substances can also be used. Phosphates, borates, especially ammonium polyphosphate, tris(tribromopentyl)phosphate, zinc borate, or boric acid complexes of polyhydric alcohols are preferred as flame retardants. Fluorescent and / or phosphorescent substances of inorganic or organic origin, especially zinc sulfite and alkaline earth aluminates, are preferred as luminescent materials.

[0072] In one embodiment of the invention, paper is used as the substrate. Paper suitable as a printing base is preferably white and has a weight of 60 to 90 g / m², more preferably 65 to 80 g / m², and particularly preferably 70 g / m². The paper is primed before printing. Suitable agents that can be used as primers are known to those skilled in the art.

[0073] Printed decorative elements are used, for example, in the production of laminate flooring or in the form of wall and ceiling cladding elements. In this case, the substrate material is preferably a wood-based panel. In one embodiment of the present invention, the substrate material is therefore a wood-based panel.

[0074] In a further embodiment of the present method, the printed substrate material, optionally provided with a protective layer, in particular of formaldehyde resins, is further processed or finished in a short-cycle (CT) press. In the CT press, the resin layers are melted and the layered composite is cured to form a laminate. During further processing in the CT press, surface structures can also be created on the surface of the substrate material, such as a wood-based panel, using a structured press plate. These structures can optionally be designed to match the decor (so-called decor-synchronous structure). In the case of wood decors, the structures can be in the form of pore structures that follow the grain. In many decors, the structures can be indentations in the area of ​​joints encompassed by the decor or filling lines.

[0075] The present invention will now be explained in more detail with reference to a figure and an exemplary embodiment. Figure 1 illustrates a basic sequence of the procedure.

[0076] Figure 1This describes a basic sequence of the method according to the invention. An analog decor 10 is provided, from which a digital image is created by the device 20, which is available in the form of decor raw data 30. According to the invention, the device 20 can be, for example, a digital camera or a scanner. The digital decor raw data 30 are processed and retouched on a PC 40, resulting in processed decor raw data 50. Three different sets of printing parameters 60-62 are provided. From the processed decor raw data 50 and one set of printing parameters 60-62 each, color space-profiled production data 70-72 are calculated. From the color space-profiled production data 70-72, separation data 80-82 are then calculated, which are subsequently used for printing on a substrate 90-92.Printing takes place using the printing parameters employed to calculate the color space-profiled production data and the associated separation data. This means that the color space-profiled production data (70) is calculated from the processed decor raw data (50) and the printing parameters (60). From the color space-profiled production data (70), the separation data (80) is calculated, and this separation data (80) is then used for printing onto the substrate (90) using the printing parameters (60).

[0077] Advantageously, color space-profiled production data 70-72 and separation data 80-82 can be generated for different sets of printing parameters 60-62, always starting from the processed decor raw data 50. The processed decor raw data 50 is in the RGB color space and thus has the highest possible information content after digitizing the analog decor 10. The color space-profiled production data 70-72 and the separation data 80-82, on the other hand, are for a color model, such as the CMYK color model.

[0078] In current technology, it is common practice to first generate separation data for specific printing parameters, which are then retouched. From this initial retouched separation data, a second set of separation data for other printing parameters is then calculated. The second set of separation data is derived from the first and is therefore also based on the color space in which the first set of separation data was calculated. Consequently, the color space of the second set of printing parameters cannot be larger than that of the first set. This approach can lead to a loss of color information and thus print quality if, for example, the first set of printing parameters covers a printer with a 4-color system and the second set covers a printer with a 5-color system. Example 1

[0079] At a manufacturer of laminate flooring planks, decors for further processing into decorative panels were printed on three different digital printing systems. Three different sets of printing parameters were therefore available for printing on each of the three digital printing systems. First, a beechwood board was provided, from which a digital image was taken with a digital camera. This digital image was thus available in the form of raw digital decor data as defined by the invention. The raw digital decor data was retouched with regard to sharpness and contrast, and processed raw decor data 50 were generated.

[0080] The three different digital printing systems comprised two identical paper-based digital printing systems on which decorative paper rolls were printed using a 4-color system. The third digital printing system was a digital printing system that printed primed wood-based panels using a 5-color system.

[0081] The color gamut was heavily influenced by the printing parameters. The white primer on the wood-based panels was significantly darker than the white paper, which meant that, with otherwise identical printing parameters, the color gamut for printing on the primed wood-based panel was initially smaller.

[0082] The substrate of the primed wood-based panel had an L-value that was 3-4 lower compared to the white paper. This resulted in a color gamut that was at least one-third smaller. The bright, vibrant colors would therefore not have been reproducible with a 4-color system (color system: CYRK). To increase the color gamut, 5 colors (5-color system) were used for printing on the wood-based panel. The 5-color system used was C Y1 Y2 RK.

[0083] From the processed decor raw data 50, color space-profiled production data 70-72 were calculated for the three different sets of printing parameters 60-62, and thus for each of the three digital printing systems, by transferring the processed decor raw data and the printing parameters 60-62 to the RIP software of the respective digital printing systems. The color space-profiled production data 70-72 for printing with the 4-color system were calculated based on the same digitally processed decor raw data as the color space-profiled production data 70-72 for printing with the 5-color system.

[0084] The following are the three sets of printing parameters for which color space-profiled production data 70-72 were calculated. Pressure parameters Sentence 1 Sentence 2 Sentence 3 Type of printing system Paper digital printing systems 1 Paper digital printing systems 2 Digital printing system for printing on wood-based panels Color model 4-color system 4-color system 5-color system (CYRK) (CYRK) (C Y1 Y2 RK) temperature 23°C 23°C 30°C Printing ink Manufacturer 1 Manufacturer 1 Manufacturer 2 Carrier material white paper white paper Wood-based panel Pretreatment of the carrier material No no white primed

[0085] For printing, separation data 80-82 were calculated from the color space-profiled production data 70-72. Printing a digital image onto the substrate was successful for all three sets of printing parameters with high quality. Furthermore, color space-profiled production data 70-72 and the resulting separation data 80-82 could be calculated quickly and efficiently for the various sets of printing parameters. Changes in printing parameters did not delay the calculation of the separation data, as this was always calculated based on the processed raw decor data. Therefore, the inventive method is more economical than prior art methods.

[0086] If the separation data for printing with the 5-color system had been calculated from the separation data for printing with the 4-color system, as is common practice in the prior art, this would have been detrimental to the quality of the separation data for printing in the 5-color system. This is because the separation data would no longer have been calculated based on the largest possible color space (the RGB color space in which the digital production data is stored), but rather on a smaller color space. Reference symbol list

[0087] 10 Analog decor 20 Device for creating a digital image 30 Raw decor data 40 PC for retouching 50 Edited raw decor data 60-62 Set of printing parameters 70-72 Color space profiled production data 80-82 Separation data 90-92 Substrate

Claims

1. Method for digitally printing a decorative pattern onto a substrate material with at least one set of defined printing parameters, wherein the method comprises the steps of i. providing an analog decorative pattern; ii. generating and storing at least one digital image, in the form of digital decorative-pattern raw data in the RGB color space, of the analog decorative pattern; iii. digitally processing at least one part of the digital decorative-pattern raw data in the RGB color space and generating processed digital decorative-pattern raw data; iv. providing at least one set of printing parameters; v. transferring the processed digital decorative-pattern raw data and the at least one set of printing parameters to color management or RIP software and computing color space profiled production data for the at least one set of printing parameters from the processed digital decorative-pattern raw data, wherein the color space profiled production data are available in a color model chosen from the group comprising CMYK, CRYK, 1-color, 5-color, 6-color, 7-color, and 8-color color models; vi. computing separation data from the color space profiled production data computed for the at least one set of printing parameters; vii. a digital printer outputting a digital image of the analog decorative pattern with the computed separation data onto a substrate material, wherein the digital printer is included in the at least one set of printing parameters for which the color space profiled production data were computed; wherein the printing parameters in the method step iv. include the type of printing system, the color model to be used for printing, the temperature, the humidity of the air, the printing ink, and the type of substrate material.

2. Method according to claim 1, characterized in that the substrate material is selected from a group comprising paper, glass, metal, foils, wood-based materials, plastics materials, and combinations thereof.

3. Method according to either of the preceding claims, characterized in that in the method step ii., the digital decorative-pattern raw data are generated by photographing the analog decorative pattern with a digital camera or by scanning the analog decorative pattern with a scanner.

4. Method according to any of the preceding claims, characterized in that in the method step iii., digitally processing the at least one part of the decorative-pattern raw data involves retouching said data.

5. Method according to claim 4, characterized in that retouching involves • changing the color tone of at least one part of the decorative-pattern raw data; and / or • changing the brightness of at least one part of the decorative-pattern raw data; and / or • changing the saturation of at least one part of the decorative-pattern raw data; and / or • changing the contrast of at least one part of the decorative-pattern raw data; and / or • changing the sharpness of at least one part of the decorative-pattern raw data.

6. Method according to any of the preceding claims, characterized in that in the method step iii., a part or all of the decorative-pattern raw data are digitally processed.

7. Method according to any of the preceding claims, characterized in that processing at least one part of the digital decorative-pattern raw data in the method step iii. is carried out using the Adobe Photoshop software.

8. Method according to any of the preceding claims, characterized in that the printing parameters in the method step iv. further include the pretreatment of the substrate material.

9. Method according to any of the preceding claims, characterized in that in the method step v., color space profiled production data are computed for more than one set of printing parameters.

10. Method according to claim 9, characterized in that in the method step vi., separation data are respectively computed from the color space profiled production data computed for each set of printing parameters, and in the method step vii., the digital image of the analog decorative pattern with the respectively computed separation data is output onto a substrate material by one digital printer each, wherein each digital printer is included in the set of printing parameters for which the color space profiled production data and the respective separation data were computed.

11. Method according to any of the preceding claims, characterized in that the substrate material is primed before printing.

12. Method according to any of the preceding claims, characterized in that the substrate material is provided with a protective layer after printing.

13. Method according to any of the preceding claims, characterized in that the substrate material is fed to a short-cycle press after printing.

14. Method according to claim 13, characterized in that the printed substrate material is provided with a surface structure in the short-cycle press.