Method and machine for digital decoration of a substrate

Abstract

The present invention relates to a method for digital decoration of a substrate, which includes applying a property-changing pattern, whereby in the area where the property-changing pattern is applied, the physical properties of the ink used for printing the pattern are changed, and the physical properties of the substrate or the physical properties of a decorative motif that may be printed on the substrate surface are thereby changed in that area. This change depends on the physical properties, number, and arrangement of the fine particles applied to and fixed to the ink. A machine for digital decoration of a substrate on which the above method is implemented is also described.

Description

Technical Field

[0001] The subject of the present invention belongs to the field of digital decoration of substrates. More specifically, methods and machines for digital decoration of substrates are described, including arranging solid powder microparticles on at least one ink surface and / or inside the ink. The microparticles are selected based on specific properties that impart different physical properties to the ink and thus to the decoration applied to the substrate.

Background Art

[0002] In the prior art, methods for digitally printing substrates are known, which can apply various decorations to substrates. This type of method can be used, for example, to decorate substrates made of various materials such as wood or wood-derived materials, plastics, metals, cement, cork, composite materials, etc., and these substrates can then be used, for example, in the manufacture of building materials such as floor, ceiling or wall panels, furniture manufacture, household appliance manufacture, etc.

[0003] The current problem is that when printing on a specific substrate with existing machines and methods, a specific decoration is simply applied to the surface. When different properties are required in specific areas of the substrate, for example, when higher wear resistance is needed, the only method currently applied in this field is to place a protective layer in those important areas.

[0004] Therefore, there is no automated method that enables quickly, automatically and effectively changing the physical properties of the printed substrate.

[0005] In the prior art, methods for digital printing are known, for example, applying a liquid binder and then applying a dye, and heat and pressure are applied to maintain the state where it is fixed to the printing surface.

[0006] Methods for modifying the surface are also known, which involve placing a liquid base on the surface and changing the thickness of the liquid base. Once changed to the desired thickness, the finally obtained liquid base is fixed. Summary of the Invention Means for Solving the Problems

[0007] The present invention relates to a method for digital decoration of a substrate and a machine for implementing the method.

[0008] The gist of the proposed method is that the visible physical properties of the decorative image are changed at specific points (or regions), thereby obtaining different optical effects, or an image that gives improved mechanical resistance or conductivity to the substrate, a design that gives a releasable fragrance to the substrate, etc. This enables changing the physical properties of the ink so as to achieve such effects. This brings an improvement over the effect of only obtaining decoration by conventional ink printing.

[0009] In order to implement a method for digital decoration of a substrate, the substrate must have a surface suitable for receiving liquid ink, either by the material of the substrate surface itself or by the fact that the surface has been pre-treated. In an exemplary embodiment of the present invention, this method is implemented on a substrate including a decorative motif. In other exemplary embodiments, the decorative motif is printed either before or after performing the steps related to the change of properties. The decorative printing can be performed by inkjet (injection printing) or other means.

[0010] In a possible exemplary embodiment, the method of the present invention includes a first step of applying a previous layer to prepare the surface of the printed area. This enables the injected ink to have particularly good adhesion to the surface. In this way, proper adhesion of the ink to the substrate is ensured, and spreading and swelling of the injected droplets are suppressed during the period from injection to fixation (using curing / drying).

[0011] This type of process may include applying one or more layers of material and / or performing some surface treatment to prepare the substrate. The substrate can be, for example, a wooden panel, a steel plate, etc. Some of the layers can be selected from a primer layer, a leveling layer, a filler layer or a pore covering layer, a primer layer, a layer that gives texture, etc. As described, there may be cases where the substrate is already suitable for receiving printing and / or no pretreatment or application of any of these layers is required. If the substrate is not properly treated and / or is not made of a material suitable for printing, the quality of the printing will be insufficient, for example, due to ink droplets moving to adjacent pixels, excessive ink absorption, etc. This can, for example, cause different colored inks to overlap in non-corresponding areas, visually blur the printed digital image, or result in a low-quality or dull-colored image.

[0012]

[0013]

[0014] ​​The microparticles are added either to the entire surface or only to a part thereof, and adhere only to the areas where the decorative ink is gelled / semi-dried. The decorative motif and the property modification pattern must be applied synchronously in order to ensure the proper quality and image accuracy of the harmonious, and thus ultimately obtained motif (a decorative motif with modified properties in at least a part of the decorative motif).

[0015] The material of the microparticles to be applied is selected based on the physical properties to be obtained. For example, the reflection properties of the ink can be changed, its resistance properties can be changed, its conductivity can be changed, its flexibility can be changed, or combinations thereof and / or others can be changed.

[0016] For this purpose, the light reflection properties of the ink can be changed, for example, by changing the glossiness, color, transparency, etc. Examples of microparticles that can be used are particles such as glitter, metal powder, pearl powder, sublimates. A specific example of the material used as pearl powder is mica coated with titanium oxide.

[0017] The microparticles can also be used to change specific functional properties of the ink such as conductivity, magnetic properties, flexibility, fragrance, etc. As another possible exemplary embodiment, it is conceivable to change the wear resistance properties, for example, by applying microparticles of aluminum oxide powder (corundum).

[0018] Therefore, by the proposed method, the physical properties of printing can be improved. Generally speaking, this method involves inkjet application of inks, varnishes or lacquers, which can be UV-curable, water-based or solvent-based, and which are colored, uncolored or a combination of both, on a substrate prepared therefor, the surface of which has been subjected to one or more preparatory treatments such as an underlayer for giving color, a layer for imparting texture, etc. Digital printing is carried out by performing the inkjet application on the surface of the substrate. The decorative motif is defined by a digital file that includes specific regions where at least one physical property of at least one ink is changed, and the printed ink acts as an adhesive for at least some of the added fine particles. The method also includes gelling / semi-drying at least one ink using UV radiation, IR radiation, hot air, etc., either for the entire applied ink or only for specific regions thereof (selective drying / curing), adding fine particles so that the fine particles remain adhered in the regions of interest where the gelling / semi-dried ink is present, removing the excess fine particles, for example by suction, and then performing complete curing or drying using UV radiation, IR radiation, hot air, etc. Also preferably, it includes brushing / cleaning by mechanical means to remove fine particles that may remain on the surface.

[0019] Throughout this specification, for the sake of simplicity, the term "ink" is used to refer to all of ink, varnish and / or lacquer. Further, as described above, the ink, varnish or lacquer can be UV-curable, water-based or solvent-based.

[0020] By adjusting the tackiness of the modified ink (i.e., the degree of gelling and / or drying applied), the degree of dispersion or penetration of the powder fine particles added thereto is adjusted.

[0021] In the case of the present invention, the ink is applied by digital processing (by an application method that does not require powder application) in a manner synchronized with the decorative motif to be formed on the substrate surface, in synchronization with the inks applied before or after each other, and also in synchronization with the property modification pattern. One difference from standard digital printing is that digital printing cannot be used for the application and fixing of fine particles. In other words, in order to obtain the desired result, in the area of the digital motif, standard single-pass printing can be performed by directly printing with the ink corresponding to the digital decorative motif, but in the area where fine particles are applied to the decorative ink to modify the properties, since the fine particles have a size that cannot be ejected, they cannot be printed with the same head as the ink.

[0022] Furthermore, the method may include sucking excess fine particles. For this purpose, the machine in which the method of the present invention is implemented may include suction means for sucking excess fine particles or particles removed by additional mechanical means. These suction means are connected to a cyclone for collecting and reusing the excess particles.

[0023] Depending on the desired properties of the substrate or a specific area thereof, one or more layers of the final treatment of lacquer or varnish (such as a protective layer or a layer for changing the degree of gloss) can be applied, depending on the desired properties, for example, by one roller or a series of consecutive rollers, by spraying, by a varnish curtain, by inkjet, etc., with the corresponding drying or curing.

[0024] In this method, it is possible to perform gelation or semi-drying on all the applied modified inks, or selectively, immediately after their application. Thus, in certain areas, the applied modified ink is completely dried or cured, while in other areas, it is not completely dried or cured. This makes it possible to select, within the ink itself, areas where the fine particles adhere and areas where they do not. Furthermore, by repeating the step of adding fine particles to the gelled / semi-dried ink as many times as necessary, it is also possible to attach different types of fine particles to a given ink.

[0025] Preferably, the fine particles attached to the gelled / semi-dried modified ink have a size of less than 20 μm. This is due to the fact that digital printing of a "binder" (i.e., the ink to be gelled / semi-dried, i.e., the ink with modified properties) places a plurality of droplets at a plurality of positions defined by the digital printing itself on the surface of the substrate to be decorated using printing. Several injectors eject ink droplets onto the substrate surface according to the digital decoration motif to be printed, and are controlled by a control device that synchronizes the digital motif to be printed and the pattern of property modification (defining the points of the digital motif where the physical properties of the ink are modified by the addition and fixation of fine particles). The plurality of injectors (through which the ink droplets are ejected) are separated from each other by a distance in units of micrometers (depending on the specific image accuracy of the injector head and / or the printer).

[0026] In single-pass type printing, a head equipped with various decorative inks for printing the digital motif is arranged so as to occupy the maximum width to be printed. The substrate moves under the head, and as it passes through, the injector head ejects ink droplets at an appropriate timing indicated by the control device based on the decorative motif to be printed.

[0027] The droplets ejected onto the substrate surface are arranged on the substrate surface at a distance determined by the spacing between the injector nozzles (forming "pixels") and form a master layout determined using a computational algorithm according to computer software. At a macroscopic level, this arrangement of ink droplets forms a design (image and / or decorative texture, i.e., an image with texture, an image only, or a texture only) that can be understood as a decorative motif.

[0028] As described above, since the distance between droplets is on the order of micrometers, if the microparticles are too large, the microparticles may occupy a space larger than the distance between pixels and interfere with each other. In this case, when another ink is ejected after fixing the microparticles, there is a risk that the ink will be ejected onto the microparticles fixed to the adjacent previously ejected ink. Therefore, when adding microparticles, if the microparticles are larger than the size corresponding to a "pixel", i.e., larger than the spacing between the nozzles of the injector, they may enter the positions that should be occupied by another color, and the fineness of the finally obtained motif will be lost.

[0029] The smaller the size of the particles, the higher the accuracy of the final decoration. However, there is also a lower limit to the size of the particles, which depends on the type of physical properties of the ink to be modified with the corresponding microparticles. In other words, a minimum particle size is required to ensure that the specific properties imparted to the final motif are continuously imparted to the ink. For example, when using corundum particles, the minimum particle size should be 10 μm.

[0030] Also, since microparticles are easily dispersed in the air, the smaller their size, the more complicated the addition becomes. This problem can be solved by dispersing the microparticles in a liquid carrier that enables these microparticles to be ejected by an ejection head and changing the application to the standard application process of ink ejection. However, here too, a lower limit of size must be considered to maintain the physical properties of the microparticles imparted to the ink being applied.

[0031] As a specific example according to the method of the present invention, there is the application of sublimable fine particles. By this, the surface on which the fine particles are fixed can be made matte by subsequent processing in which energy required for sublimation is supplied. The sublimation results in the microstructuring of the ink to which the sublimable fine particles are fixed, bringing about a matte effect, i.e., a change in the light reflection characteristics of the ink to which the fine particles adhere.

[0032] Another related factor is the weight per unit area, i.e., the number of fine particles applied per unit surface area. In certain cases, especially when changing the reflection characteristics of the ink, the number of fine particles applied to a given ink area must not exceed a predetermined threshold. By doing so, it is possible to prevent the loss of the original optical characteristics of the ink. In one example that can be considered, in order to produce a nacreous luster effect in a specific area of a digital image, nacreous fine particles with a weight per unit area of 2 - 4 g / m 2 are applied. Thereby, a nacreous luster effect of the color in the region of interest can be obtained without erasing the applied color itself.

[0033] The method of the present invention is a very versatile method because it can be adapted to the specific requirements of each substrate and / or the specific requirements of each decorative motif to be printed.

[0034] For example, when only changing the physical properties of an ink of a certain color, other decorative inks can be injected and completely dried, and before or after that, a coloring modifying ink can be applied, where only gelation and addition of fine particles can be carried out. Thereafter, the remaining steps are carried out as usual (for example, removal of excess fine particles, complete curing of the ink itself, cleaning of residues using, for example, flashing, application of a protective varnish, etc.).

[0035] Before printing the decorative ink, regardless of whether it is colored, when printing a decorative motif consisting of multiple inks, gelling or semi-drying can be performed between the injection of each different ink. That is, it is not necessary to completely cure / dry each of these inks. In fact, in a preferred embodiment, all previously injected colored inks are completely cured / dried after the application of the last ink and before printing with the property-changing pattern ink.

[0036] After applying the microparticles to the gelled or semi-dried decorative ink and after sucking off the excess microparticles, if another decorative motif is printed or printed with some other inks, the step of completely curing / drying the decorative ink with microparticles can be excluded, provided that there is no need for subsequent mechanical brushing that may remove the semi-cured or semi-dried decorative ink already equipped with microparticles there. Thereby, the surface receives the next ink with the decorative ink in this state. This embodiment can ensure better adhesion between the inks.

[0037] However, when changing the physical properties with inks of various colors, it may be more convenient to perform a complete digital print of the decorative motif and the corresponding complete drying / curing. Subsequently or previously, a transparent decorative ink is applied to the specific area where the physical properties are changed, and microparticles are added to the surface of that area. More specifically, the addition of microparticles is performed over the entire surface of the substrate (or at least a relatively large area compared to the area where it is actually fixed), and only what has fallen onto the gelled or semi-dried decorative ink is retained on the substrate surface.

[0038] Similarly, it may be possible to modify some physical properties across the entire surface of the substrate. In that case, without previously printing a specific digital image, it is necessary to apply a transparent decorative ink across the entire surface, incompletely gel / dry it, then apply the desired microparticles, and fully cure / dry it. These same steps can also be performed by generating a dispersion of microparticles in an ink, varnish, or lacquer and applying it across the entire surface by means other than digital printing, such as a roller or curtain (since application is not possible due to the particle size). By these means, it becomes possible to apply the dispersion more freely with respect to the particle size, but there is a drawback in that the application area cannot be accurately selected.

[0039] In another exemplary embodiment of the present invention, the method of the present invention may include the implementation of texture imparting. This texture imparting is performed by a removal means and includes, for example, brushing in the layer to which the texture is imparted, applying an ink for imparting texture to the surface, then gelling / semi-drying the layer and the ink, performing texture imparting, and finally fully drying / curing the textured layer. These steps are preferably performed before applying the microparticles.

[0040] In another possible embodiment, the steps corresponding to texture imparting of the layer to which the texture is imparted are repeated to create additional textured areas. In this case, the steps regarding property modification by applying microparticles can also be repeated.

[0041] Another object of the present invention is a machine for digitally decorating a substrate according to the method described above. The machine includes at least an ejection head for ejecting ink, a curing means and / or a drying means, an addition head for adding microparticles and sucking excess microparticles, a mechanical cleaning means (optionally), and a control device configured to synchronize / adjust a decorative motif and a property modification pattern and control the remaining elements according to the synchronization.

[0042] When texture is also to be imparted, the machine also includes at least one means for imparting texture, which can be, for example, a brush.

[0043] In short, the decorative motif is printed with ink, which may or may not be colored, and at least one of the inks (decorative ink) is gelled / semi-dried so as to act as an adhesive for the microparticles that are subsequently applied to the decorative motif. Since the microparticles are small (but large enough not to be injectable with a standard inkjet head), it is very convenient to sprinkle them over the entire surface, but the microparticles are trapped only in the areas where the decorative ink is gelled / semi-dried. Thus, the method includes subsequently sucking off the excess microparticles.

[0044] Thus, in a first aspect of the invention, a method for digital decoration of a substrate having a surface is proposed. The method of digital decoration of the substrate comprises a) injecting a decorative ink by digital application at predetermined points on the surface of the substrate corresponding to specific points that make up the characteristic change pattern; b) gelling or initially drying the decorative ink to thereby obtain a predetermined degree of gelling or drying; c) adding microparticles having specific physical properties to the surface of the substrate provided with the decorative ink, such that some of the microparticles remain attached to the gelled / semi-dried decorative ink and change the physical properties of the decorative ink at the points that make up the characteristic change pattern; d) sucking off the microparticles that have not adhered to the decorative ink after applying the microparticles; e) incompletely or completely curing or drying the decorative ink with the microparticles and including.

[0045] Preferably, the microparticles added have a size of up to 20 μm.

[0046] In a more detailed embodiment, the surface on which the decorative motif is printed is already suitable or pre - prepared to receive at least one liquid ink, and the method of the present invention comprises - printing the decorative motif by injecting a decorative ink onto the substrate surface, whether it is colored or not; - after each injection of the decorative ink, drying / curing the injected decorative ink; - performing steps a) to e); and includes.

[0047] After each injection of the decorative ink, the step of drying / curing the injected decorative ink may include complete or incomplete drying / curing of each previously injected ink. In this case, the method of the present invention includes an intermediate step of completely drying / curing the ink injected onto the surface of the substrate before performing steps a) to e).

[0048] In another exemplary embodiment, the step of gelling or semi - drying the decorative ink is incomplete, and the remaining portion of the decorative ink is completely cured or dried, so that the microparticles added later remain adhered only to the gelled or semi - dried region of the decorative ink.

[0049] Similarly, steps a) to e) are repeated as many times as necessary depending on the characteristic change pattern, the number of different decorative inks, and / or the physical properties that are varied for each of the plurality of decorative inks.

[0050] In one embodiment of the present invention, a step of mechanically cleaning by contacting with the microparticles not fixed after drying or curing in step e) is performed.

[0051] In other exemplary embodiments, as described above, the method of the present invention, before steps a) to e), - applying a texture - giving layer; - optionally, incompletely drying or curing the texture - giving layer. - applying ink to impart texture; - gelling / semi-drying the layer and the ink for imparting texture; - performing texturing brushing; - completely drying or curing the layer already imparted with texture; and may include.

[0052] Similarly, this method includes f) applying a finishing layer or finishing varnish to the surface of the substrate; g) drying or curing the finishing layer or finishing varnish; and may further include.

[0053] By applying a finishing layer or finishing varnish, it is possible to impart to the substrate, for example, specific aesthetic appearances such as greater abrasion resistance, matte finish or gloss.

[0054] As described above, in a preferred embodiment, the added microparticles are sublimable.

[0055] Similarly, in a preferred embodiment, the movement of the substrate, the injection of decorative ink, the injection of finishing ink, and the direction of travel of the spraying of microparticles are continuously controlled so as to ensure synchronization between the printed digital motif and the characteristic change pattern.

[0056] In a second aspect of the present invention, a machine for digital decoration of a substrate by the method described above is proposed. This machine includes conveying means for moving the substrate, an injection head for ink injection, curing and / or drying means, an addition section including an addition head and at least one suction head for subsequently sucking up non-attached microparticles, and a control device configured to synchronize the application of the decorative motif and the characteristic change pattern and control the movement of the conveying means and the remaining elements based on that synchronization.

[0057] Preferably, the machine also includes application means (e.g., different application means for applying multiple layers of liquid material, etc.) for applying a preparation material of one or more substrates, and first drying / curing means. Further, it may include application means for applying a finish layer to the substrate and final drying / curing means configured to cure / dry the finish layer applied thereon. Also preferably, each curing and / or drying element is arranged behind the ink injection head and configured to cure / gel and / or semi-dry / dry at least the type of ink ejected by the previous ink injection head.

[0058] Preferably, the machine also includes application means for applying a layer to which texture is imparted and application means for applying ink to which texture is imparted. Also included is a means for imparting texture, which can be, for example, a brush.

[0059] Throughout this specification, the term "substrate" is usually used for individual substrates, for example, generally boards, panels, sheet metals or unit pieces, particularly chipboards, medium density fiberboards (MDF, HDF), fiber cement boards or the like, for example plastic panels or sheets made of PVC, and sheets or panels of composite materials such as LVT (luxury vinyl tile), SPC (stone plastic composite), WPC (wood plastic composite) etc. which are currently widely used in the flooring manufacturing industry, for example metal panels or sheets such as aluminum, steel, etc., cork panels or sheets.

[0060] Also, the term "substrate" includes continuous materials supplied and affixed in a roll or strip form, such as rolls of thin wood veneer, rolls or coils of steel, paper, plastic, cork, etc. As a specific case for applying materials having these features according to the present invention, the roll material is stretched to apply the method of the present invention thereto, and preferably, subsequent recovery is performed by rewinding.

Brief Description of the Drawings

[0061] For the purpose of making the description complete and helping to more easily understand the features of the present invention, a set of drawings constituting an integral part thereof is attached to this specification, and the drawings show, by way of non-limiting example, the following.

FIG. 1A - B

FIG. 2A - B

FIG. 3

FIG. 4A - B

Embodiments for Carrying Out the Invention

[0062] The present invention should not be limited to the embodiments described in this specification. Other configurations can be implemented by those skilled in the art based on this specification. Therefore, the scope of the present invention is defined by the appended claims.

[0063] Figures 1A - B show a method for digital decoration of a substrate in which different types of inks are used. After applying each ink, corresponding UV or IR curing / drying is performed. In both Figures 1A - B, a preliminary step of applying a preparation layer (0) or a primer is carried out. In Figure 1A, the primer is solvent-based, water-based, etc., and drying by evaporation (1) is used for pre-drying. In Figure 1B, for example, a polymerizable primer is used and pre-curing (6) is performed for its fixation.

[0064] After that, in both cases, steps of applying different inks (2.1, 2.3, 2.5, 7.1, 7.3, 7.5) and steps of drying / curing each of the inks after the application (2.2, 2.4, 2.6, 7.2, 7.4, 7.6) are executed. The example in FIG. 1A shows that curing is performed using a UV lamp (2.2, 2.4, 2.6). The example in FIG. 1B shows that drying is performed using an IR lamp (7.2, 7.4, 7.6).

[0065] After these steps, step a) is performed by injecting a decorative ink, which may or may not be colored, onto a predetermined point on the substrate surface corresponding to a specific point of the decorative motif constituting the characteristic change pattern, by means of a digital coating head (3.1, 8.1) using an injection head. After this injection of the decorative ink, step b) is executed, which includes gelling (3.2) (for example, by applying UV radiation as in FIG. 1A) or first drying (8.2) (semi-drying) (for example, by evaporation by applying IR (infrared) radiation as in FIG. 1B).

[0066] In step c) of the method of the present invention, addition of fine particles used to change the characteristics of the decorative motif is performed. The fine particles are applied covering the entire surface of the substrate advancing under the corresponding head. Depending on the size of the head, they are applied as a "particle curtain" that falls across the entire width of the substrate surface. It is possible to increase or decrease the number of coatings per unit area (weight per unit area), and it is possible to control whether to apply to the entire substrate or only to some regions. If it is possible to apply only to some regions, since the size of the fine particles is small, it is very complicated and not feasible to apply only to specific points, so it involves relatively large regions.

[0067] FIGS. 1A - B show how the application of fine particles (3.3, 8.3) is performed in both cases and how step d) is performed, that is, the method of sucking excess fine particles that do not adhere to the decorative ink (they adhere only in the regions where the decorative ink has gelled or semi-dried).

[0068] Since some of the microparticles remain attached to the gelled / semi-dried modified ink, it changes the physical properties of the modified ink at the specific points, synchronized with the printed digital motif that constitutes the property change pattern.

[0069] Subsequently, the curing / drying of the modified ink is completed (step g)), and the microparticles are already fixed there (3.4, 8.4). Again, the type of fixation depends on the type of modified ink being applied. In these examples, curing using UV (ultraviolet) electromagnetic radiation (3.4) and another drying using IR (infrared) electromagnetic radiation (8.4) are shown. Figures 1A - B also show the mechanical cleaning after fixation (step e)), which ensures the proper removal of any remaining excess microparticles if some remained after the initial suction.

[0070] As can be seen from these figures, different fixation mechanisms are preferably selected for the primer and the ink to avoid interference between the fixations used in each case. These fixation mechanisms can also be the same process if the primer, ink and / or their fixing devices are appropriately designed for that purpose.

[0071] Steps a) - e) can be included as steps performed in each property change cycle (3, 8). When applying different types of modified ink, it is necessary to repeat these steps to obtain changes in multiple properties of the decorative motif.

[0072] As shown in the figure, the step of applying the topcoat or finishing varnish (4) and the final curing / drying step (5) can be subsequently carried out to fix the top layer or varnish.

[0073] Furthermore, the gelling or semi-drying (3.2, 8.2) of the decorative ink can be applied to the entire decorative ink (3.1, 8.1) or can be selectively carried out. In this second case, some areas of the decorative ink are fully cured / dried and the gelling / semi-drying is applied to the remaining areas. In this way, when the microparticles are applied, they adhere only to a part of the applied decorative ink.

[0074] Figures 2A - B show, for example, an exemplary embodiment of a method of applying different types of microparticles to the same decorative ink (e.g., a colored ink, so as to obtain different properties with the same color). In this case, the decoration cycle (3, 8) is repeated, with the application of the same type of decorative ink being repeated, followed by the application of microparticles with different properties.

[0075] Figure 3 shows another exemplary embodiment. In this case, one method of the present invention is shown, where a preparation layer (0) is applied, which is a primer in this case, and the first drying or curing (1) of the preparation layer is carried out by evaporation in this case. Next, color decoration is applied by a digital printer (9.1, 9.3, 9.5, 9.7), and after the application, each ink is cured / dried (9.2, 9.4, 9.6, 9.8). This curing / drying, as shown in the figure, is followed by complete curing / drying (10) after the step of applying and curing / drying the ink (9), so it can be complete or incomplete. In another exemplary embodiment, instead of the preparation layer (0), a textured layer (0) is applied.

[0076] Next, the application of the decorative ink (3.1), the gelling thereof (3.2), and the application of the microparticles (3.3) are carried out, and the microparticles that do not adhere to the decorative ink are suctioned. In this exemplary embodiment, the microparticles can provide a metallic visual effect in the selected area (where the decorative ink is applied). The step of fully curing the decorative ink (3.4) is also carried out, and any remaining microparticles are removed by a mechanical method (3.5).

[0077] Finally, a protective layer (4) (or finish varnish) is applied and curing (5) is performed, in which case complete UV curing of the image obtained with the protective layer (image printed with ink and decorative ink) is carried out.

[0078] In this exemplary embodiment (Figure 3), the intermediate curing (9.2, 9.4, 9.6, 9.8) is incomplete curing, so a gelled state is obtained there. Complete fixation between the plurality of colors (the different inks (9.1, 9.3, 9.5, 9.7) applied) is not required because they are fixed last before applying the decorative ink and the microparticles. In this case, the decorative ink can be a transparent ink, which is applied, for example, to some areas of the previously applied color, so that when the microparticles are applied, the microparticles remain attached to the transparent ink layer, changing the design characteristics of the portion where the microparticles are fixed.

[0079] Figure 4A shows another possible embodiment of the present invention where texture is imparted. As shown in the figure, the method includes performing step (0) before applying the layer to which texture is imparted, and optionally pre-drying / pre-curing (6) is carried out. Next, ink (11.1) for imparting texture is applied, curing (11.2) is performed, and a specific texture is obtained by means of removal (12) to give texture, and complete drying / curing (13) of the layer already imparted with texture is carried out. When texture is imparted to the desired area of the substrate surface, inks (11.3, 11.5) are applied and incompletely gelled / cured (11.4, 11.6), and the substrate passes through the modification cycle (3), where it is printed with the ink to be modified and microparticles are applied to that ink to be modified. The final step is the same as already described for the method of the present invention, i.e., a finish layer or finish varnish (4) is applied and final curing / drying is carried out (5) to fix the top layer or varnish.

[0080] In another exemplary embodiment shown in FIG. 4B, another layer (0) is applied after the finishing cycle (3) to which texture is imparted, and all the steps described above can be repeated again. At the end of the method, as in the previous case, a finishing layer or finishing varnish (4) is applied and final curing / drying (5) is performed. FIG. 4B shows an example in which a layer (0) to which texture is imparted is applied, optionally a first drying (6) is performed, ink (11.1) for imparting texture is injected, both the layer and the ink are gelled / semi-dried (11.2), and then texture application (12) with a brush and curing (13) of the layer already imparted with texture are performed. Then different inks (11.3, 11.5) are applied and corresponding drying (11.4, 11.6) is performed. After these steps are carried out, in the finishing cycle (3), steps a) to e) of the method of the present invention are carried out. In this example, application of an additional layer (0) to which texture is imparted is subsequently carried out, and that additional layer (0) to which texture is imparted is optionally cured by a first curing (6), another ink (11.7) for imparting texture is applied, corresponding gelling / semi-drying (11.8), subsequent texture application (12) for imparting texture thereto, and complete curing (13) are carried out so that all steps are repeated again. After these steps, an additional ink (11.9) can be applied and cured correspondingly (11.10), and steps a) to e) are carried out in another finishing cycle (3). Finally, a protective layer or protective varnish (4) can be applied and final complete drying (5) is performed.

[0081] Similarly, FIGS. 1A - B, 2A - B, 3 and 4A - B show different exemplary embodiments of machines for digital decoration of substrates, which are also the subject of the present invention. As shown in the figures, there are common elements in all embodiments, and then, depending on the type of ink used, the elements are changed, added or rearranged. For example, when aqueous ink is used, drying means including drying by evaporation are used, and when polymerizable ink is injected, means for curing or polymerization such as electromagnetic radiation, particularly UV, are used.

[0082] Part of the mechanical elements for digital decoration of the substrate of the present invention includes conveying means for moving the substrate, injection heads (2.1, 2.3, 2.5, 3.1, 7.1, 7.3, 7.5, 9.1, 9.3, 9.5, 9.7, 8.1, 11.1, 11.3, 11.5, 11.7, 11.9) for ink injection, curing and / or drying means (2.2, 2.4, 2.6, 3.2, 3.4, 7.2, 7.4, 7.6, 8.2, 8.4, 9.2, 9.4, 9.6, 9.8, 10.11, 2.13, 11.4, 11.6, 11.8, 11.10), and an application section (3.3, 8.3) including an application head for applying microparticles by addition and subsequent suction of non-adhering microparticles and at least one suction head. Similarly, the machine includes a control device configured to synchronize the decorative motif and the characteristic change pattern and control the movement of the conveying means and the remaining elements based on the synchronization.

[0083] Preferably, as shown in the figures, the machine further includes application means (0) for applying a primer or preparing the substrate, and first drying / curing means (1.6).

[0084] The machine may further include application means (4) for applying a finish layer or top layer configured to apply a finish layer, for example a protective layer, to the substrate surface, and final drying / curing means (5) configured to cure / dry the previously applied finish layer.

[0085] Furthermore, as described, in the exemplary embodiments, after each ink ejection head (2.1, 2.3, 2.5, 3.1, 7.1, 7.3, 7.5, 8.1, 9.1, 9.3, 9.5, 9.7, 11.1, 11.3, 11.5, 11.7, 11.9), there is disposed a respective curing and / or drying means (2.2, 2.4, 2.6, 3.2, 7.2, 7.4, 7.6, 8.2, 9.2, 9.4, 9.6, 9.8, 11.2, 11.4, 11.6, 11.8, 11.10, 13) configured to cure / dry the type of ink ejected by the previous ink ejection head (2.1, 2.3, 2.5, 3.1, 7.1, 7.3, 7.5, 8.1, 9.1, 9.3, 9.5, 9.7, 11.1, 11.3, 11.5, 11.7, 11.9). Also preferably, the machine comprises at least one removal means, which includes at least one brush (12) for applying texture to the textured layer (0).

Explanation of Signs

[0086] 0 Preparation layer or textured layer 1 Drying or curing of the preparation layer 2.1, 2.3, 2.5 Steps of applying ink 2.2, 2.4, 2.6 Steps of drying / curing ink, UV lamp 3 Characteristic change cycle, modification cycle 3.1 Digital application using a modification ink ejection head, modification ink 3.2 Gelation or semi-drying of the modification ink 3.3 Application of microparticles 3.4 Curing / drying of the modification ink 3.5 Removal of microparticles by mechanical means 4 Steps of applying a finish layer or finish varnish 5 Final curing / drying step 6 Pre-drying / pre-curing 7.1, 7.3, 7.5 Steps of applying ink 7.2, 7.4, 7.6 Steps of drying / curing ink, IR lamp 8 Characteristic change cycle, modification cycle 8.1 Injection Head, Decorative Ink 8.2 Gelation or Semi-Drying of Decorative Ink 8.3 Application of Particles 8.4 Curing / Drying of Decorative Ink 9 Steps of Applying Ink for Curing / Drying 9.1, 9.3, 9.5, 9.7 Application of Color Decoration 9.2, 9.4, 9.6, 9.8 Intermediate Curing / Drying 10 Complete Curing / Drying 11.1 Ink for Providing Texture 11.2 Curing 11.3, 11.5 Ink 11.4, 11.6 Incomplete Gelation / Curing 12 Texture Application by Removal Means, Removal Means 13 Complete Drying / Curing of Textured Layer

Claims

1. 1. A method for digitally decorating a surface of a substrate, the method comprising: a) ejecting, by digital application, a modified ink onto predetermined points on the surface of the substrate that correspond to specific points that make up a property-altered pattern; b) gelling or initial drying of said modified ink to obtain a predetermined degree of gelling or drying; c) adding particulates with specific physical properties to the surface of the substrate carrying the modified ink, so that some of the particulates remain attached to the gelled / semi-dried modified ink and modify the physical properties of the modified ink in a manner that constitutes the property-modified pattern; d) after applying the particles, aspirating the particles not adhering to the modified ink; e) partially or completely curing or drying the modified ink comprising the microparticles; A method comprising:

2. The method of claim 1 , wherein the substrate includes a decorative motif and the property-altering pattern is synchronized with the already printed decorative motif.

3. Before performing step a), - printing a decorative motif by ejecting decorative ink onto the surface of said substrate; - after each ejection of said decorative ink, curing / drying said ejected decorative ink; The method of claim 1 , comprising:

4. The method of claim 1 , further comprising at least one step of printing a decorative motif on a surface of the substrate, the decorative motif being synchronized with the property-altering pattern.

5. 10. The method of claim 1, wherein the microparticles have a maximum average size of 20 μm.

6. 4. The method of claim 3, wherein the step of curing / drying the jetted decorative inks can include complete curing / drying or incomplete curing / drying of each previously jetted ink, and in the case of incomplete curing / drying, includes an additional step of complete curing / drying the ink jetted onto the surface of the substrate.

7. 2. The method of claim 1, wherein in step b) the modified ink is partially gelled or semi-dried, and the remaining portion of the modified ink is fully cured or dried such that the deposited microparticles in step c) only adhere to the gelled or semi-dried areas of the modified ink.

8. 2. The method of claim 1, wherein steps a) through e) are repeated as many times as necessary depending on the property modification pattern, the number of different modified inks, and / or the physical properties to be altered for each modified ink.

9. 2. The method of claim 1, wherein step e) is followed by a step of mechanically cleaning by contact the particulates that are not fixed after the drying or curing of step e).

10. f) applying a finishing or top layer or a finishing or top varnish to the surface of the substrate; g) drying or curing the finishing layer or the finishing varnish; The method of claim 1 further comprising:

11. The method of claim 1 , wherein the added particulates are sublimable.

12. 2. The method of claim 1, wherein the substrate movement, the modified ink ejection, and the microparticle addition directional control are continuously performed to ensure synchronization between the printed digital motif and the property modification pattern.

13. 12. The method of claim 12, 3, 12 and 4, or 12, 3 and 4, further comprising controlling the projection of the decorative ink onto the surface of the substrate.

14. 2. The method of claim 1, wherein the initial treatment of the substrate comprises applying a preparatory layer (0) and / or a textured layer (0).

15. 15. The method of claim 14, comprising first drying or curing the preparation layer and / or the textured layer (0).

16. 15. The method of claim 14, further comprising applying the textured layer (0) followed by applying a texturing ink (11.1), gelling / semi-drying (11.2) of the textured layer (0) and the texturing ink, removing (12) and fully drying / curing (13) the texturing before steps a) to e).

17. 17. The method according to claim 16, wherein steps a) to e) are followed by applying a further textured layer (0), printing a further texturing ink (11.7), incomplete gelling / semi-drying (11.8) of said further textured layer and said further texturing ink, texturing (12) and complete drying / curing (13).

18. 10. A machine for the digital decoration of a substrate according to the method of claim 1, comprising conveying means for moving said substrate, an ejection head (2.1, 2.3, 2.5, 3.1, 7.1, 7.3, 7.5, 8.1, 9.1, 9.3, 9.5, 9.7, 11.1, 11.3, 11.5, 11.7, 11.9) for ejecting ink, and hardening and / or drying means (2.2, 2.4, 2.6, 3.2, 7.2, 7.4, 7.6, 8.2, 9.2, 9.4, 9. 11.6, 11.8, 11.10), an application section (3.3, 8.3) including an application head and at least one suction head for adding the fine particles and subsequently suctioning off the unattached fine particles, and a control device configured to synchronize the decorative motif with the property-changing pattern and to control the movement of the conveying means and the remaining elements based on said synchronization.

19. 19. Machine according to claim 18, further comprising application means for applying a preparatory layer (0) and first drying / curing means (1.6).

20. 19. The machine according to claim 18, further comprising a finishing layer application means (4) configured to apply said finishing layer to the surface of said substrate, and a final drying / curing means (5) configured to cure / dry said previously applied finishing layer.

21. Each of said curing and / or drying means (2.2, 2.4, 2.6, 3.2, 7.2, 7.4, 7.6, 8.2, 9.2, 9.4, 9.6, 9.8, 10, 11.2, 11.4, 11.6, 11.8, 11.10, 13) is connected to an ink ejection head (2.1, 2.3, 2.5, 3.1, 7.1, 7.3, 7.5, 8.1, 9.1, 9.3, 9.5, 9.7, 11.1, 11.3, 11.4, 11.5, 11.6, 11.8, 11.10, 13).

19. Machine according to claim 18, wherein each curing and / or drying means is arranged after a previous ink ejection head (2.1, 2.3, 2.5, 3.1, 7.1, 7.3, 7.5, 8.1, 9.1, 9.3, 9.5, 9.7, 11.1, 11.3, 11.5, 11.7, 11.9), and wherein each curing and / or drying means is arranged to cure / dry an ink of the type ejected by a previous ink ejection head (2.1, 2.3, 2.5, 3.1, 7.1, 7.3, 7.5, 8.1, 9.1, 9.3, 9.5, 9.7, 11.1, 11.3, 11.5, 11.7, 11.9).

22. 19. The machine according to claim 18, further comprising a removal means (12) configured to apply a texture to the surface of the textured layer (0).

23. 23. A machine as claimed in claim 22, wherein said removing means (12) comprise at least one brush.

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