Method for printing a substrate using inkjet printing

Abstract

The invention relates to a method for printing a substrate using inkjet printing. In order to provide a method for printing a substrate using inkjet printing, which achieves substrate printing efficiently and simply, in which the printing result is particularly uniform and free from disturbances, and in particular regions with significant visual differences are avoided, it is proposed herein that inked areas are given on the substrate, in particular in an inked area grid composed of inked area rows and inked area columns, wherein a single pattern composed of at least two droplets is printed for each inked area by means of a printing head nozzle of at least one printing head, for which purpose the printing head nozzle and the substrate surface are moved relative to one another during the printing process, in particular along an imaginary nozzle trajectory. Within at least a portion of the single pattern, preferably within each single pattern, the droplets are printed on the substrate in such a way that the mutual influence of the droplets within the single pattern is counteracted.

Description

Technical Field

[0001] This invention relates to a method for printing on a substrate using inkjet printing. Background Technology

[0002] Various techniques for printing substrates using inkjet printing have been disclosed in the prior art and applied to a wide range of applications, such as printing rigid and flexible substrates. This inkjet printing method is particularly suitable for specific applications that require the precise placement of a precise amount of functional liquid into several precisely defined surface areas (corresponding ink application areas) of the substrate. Such applications include, for example, process or medical sensor surfaces, reactive surfaces for medical applications, or pixel surfaces of displays such as LCDs, TFTs, OLEDs, or electronic paper.

[0003] Especially when printing RGB patterns as color filters onto electronic paper displays, a large number of inked areas are typically printed. The size of each individual pattern to be printed can vary considerably, ranging from very small (e.g., 40 × 40 μm) to large (e.g., 200 × 1000 μm). A typical size for a single pattern is approximately 60 × 200 μm. To achieve color display using electronic paper, the printed color layers are visible in the white areas of the underlying electronic paper, particularly the red (R), green (G), and blue (B) pixel faces that act as filters. The black electronic paper pixels absorb light, making the printed RGB color filters only very faintly visible, thus these electronic paper pixels appear almost colorless. For color electronic paper, a pixel typically consists of three color subpixels (RGB) and possibly another white subpixel forming a high-resolution pixel array. Each (color) subpixel is an inked area for printing, and each color has a specific inked area type.

[0004] To achieve high-quality printing results, especially high-quality electronic paper surfaces, it is necessary to uniformly construct sub-pixels across the entire surface of the substrate. The positioning and size of the pixels, as well as the amount of color filters released into each sub-pixel, which serves as the ink-receiving area within narrow boundaries, are all of great importance.

[0005] To achieve repeatable and interference-free printing results, the commonly used quantitative method in inkjet printing applications is to place exactly the same amount or number of inkjet droplets in each ink zone of an ink zone type, that is, in all ink zones with the same function, color, shape and / or size.

[0006] An observer's eye can very keenly detect differences in intensity in the substrate, especially in the case of color filters in electronic paper, particularly when several printed single patterns are side by side and / or have similar defect characteristics that are slightly different from the remaining single patterns in adjacent areas.

[0007] In practice, these subtle differences are often caused by inherent fluctuations in the printhead nozzles. Specifically, when the printing area differs, even with identical ink volumes, the visual impression of a sub-pixel remains significantly different from the others. Conversely, even with the same area but slight differences in ink volume, the impression remains remarkably different. Therefore, fluctuations in printhead nozzle position that cause area variations, and / or fluctuations in ink volume, can both lead to these undesirable effects.

[0008] The arrival of droplets with a single pattern at different times on the substrate can also result in several different visual impressions of a single pattern, because the printing medium may not be absorbed on the substrate immediately, and the surface tension effect of freshly printed droplets may cause the printing medium to flow systematically toward previously printed droplets. Summary of the Invention

[0009] In view of this, the object of the present invention is to provide a method for printing on a substrate using inkjet printing, which achieves printing on the substrate efficiently and simply, wherein the printing result is particularly uniform and interference-free, and wherein areas with significant visual differences are particularly avoided.

[0010] The solution of the present invention to achieve the above-mentioned objective lies in the method described below. Advantageous improvements of the present invention are further described in the following summary of the invention.

[0011] In the method of printing on a substrate using inkjet printing according to the present invention, ink zones are defined on the substrate, particularly in an ink zone grid composed of rows and columns of ink zones. A single pattern consisting of at least two droplets is printed on each ink zone using a printhead nozzle of at least one printhead. For this purpose, the printhead nozzle and the surface move relative to each other during the printing process, particularly along an imaginary nozzle trajectory. Droplets are printed on the substrate in a manner that counteracts the mutual influence of droplets within the single pattern, preferably within each of the single patterns, in at least a portion of the single pattern.

[0012] The method of this invention advantageously achieves particularly uniform and interference-free printing results because the mutual influence of droplets within a single pattern is minimized. Consequently, each droplet individually and in the same manner contributes to the overall visual result. This is particularly relevant when printing a single pattern consisting of far more than one droplet onto a substrate surface, as in this case, at least two identical droplets are always arranged adjacently, which can easily lead to significant and frequent interference with the printed image.

[0013] Printing, in principle, refers to a method in which a liquid or flowable printing medium is applied to a surface, wherein the application is performed according to a stencil, a given pattern, and / or at a given location. According to the invention, the printing method is inkjet printing, i.e., matrix printing, in which the printing medium to be applied is applied to a substrate in the form of droplets or as jets. Accordingly, it is preferably non-contact, i.e., printing is performed in a manner in which the printing apparatus does not directly contact the substrate.

[0014] Printing is performed using one or more printheads, wherein the printheads are movable relative to the substrate to be printed during the printing process to print at different positions on the substrate. This can be achieved either by fixing the printheads and allowing the substrate to move, or vice versa. In principle, the printhead has at least one printhead nozzle for releasing droplets or a jet of printing media. Preferably, a large number of printhead nozzles are arranged in a row on the printhead, and particularly preferably arranged at equal intervals. Alternatively, the printhead nozzles can be arranged in several rows on the printhead, particularly sequentially along the printing direction and / or laterally staggered. Particularly preferably, the rows of printhead nozzles are laterally staggered in a certain way, such that all nozzle trajectories of the printhead have the same distance from each other, thereby achieving uniform lateral resolution.

[0015] During printing, and preferably during each pass of the printhead relative to the substrate surface, the substrate surface below the area of ​​the printhead nozzles is referred to as the printhead trajectory, and the vertical projection of each individual printhead nozzle onto the substrate surface of the motion trajectory realized during printing is referred to as the nozzle trajectory. Accordingly, the nozzle trajectory is not necessarily physically mapped onto the substrate, but is initially an imaginary trajectory. If the printhead continuously releases printing medium during its linear movement through the maximum printing range or along the ink zone row, the nozzle trajectory is reflected by the printing medium on the substrate surface. The nozzle trajectory can, in principle, extend linearly, or have any other non-linear orientation, and / or may be at any angle to the ink zone row or column. According to a particularly preferred embodiment of the method, the method is implemented in an alignment-free manner, i.e., without aligning the substrate relative to the printhead nozzle trajectory (particularly according to alignment features) before printing. During a single pass through the substrate, a printhead comprising several printhead nozzles arranged in a row generates several imaginary nozzle trajectories within the substrate surface area, wherein the distance between the nozzle trajectories corresponds to the original lateral resolution of the printhead.

[0016] The printing medium, applied as droplets onto the substrate during the printing process, can in principle be any liquid and can be used for any purpose. The printing medium can be based on aqueous or non-aqueous solvents and may also contain any other functional components, such as dyes and pigments, but may also contain substances with chemical and / or biochemical activity. Particularly preferably, the printing medium is an ink or color filter dye solution used for printing sub-pixels of a display.

[0017] The substrate can, in principle, be made of any material and have any shape. Preferably, the substrate has a flat, printable surface, and particularly preferably employs a flat construction, especially as a plate or thin film. The substrate can be either rigid or flexible. An example of a flexible substrate is a flexible EPD (electronic paper display), which, as an unprinted substrate, has a native black / white resolution of 150 ppi and a TFT pixel size of 170 μm. To generate a color display based on this EPD, RGB filters are printed from top to bottom onto each black / white TFT pixel, where each color pixel is typically slightly smaller than the TFT pixel size, for example, only 150 μm. In this case, the resulting color display resolution is, for example, 75 ppi. Preferably, several, for example, four, inking grids are provided on the surface of the substrate in a staggered manner, wherein one grid is printed with a red filter, one grid with a green filter, one grid with a blue filter, and the fourth grid remains unprinted. More preferably, each TFT pixel has at least one ink area of ​​an ink area type (e.g., color).

[0018] A key criterion for high quality is that color pixels are precisely placed in a given location within each TFT pixel. These nominal locations are typically defined by the substrate, for example, as recesses in the substrate or as TFT grids, forming ink areas. While other applicable standards may exist, a fundamental condition in most cases is that, for all pixels in an active matrix display, color pixels or subpixels within a TFT pixel are not allowed to encroach on adjacent TFT pixels; instead, they must remain within the TFT pixel area.

[0019] Accordingly, the inked area is the underlying structure within the display, such as the TFT driving pixel of the display, wherein, preferably, the inked area is printed with exactly a single pattern. In principle, the inked area can be practically given on the substrate, or the inked area only represents a specific location on the entire surface, and these locations are not directly visible on the substrate itself. A substrate can have one or more different inked area types. Different inked area types can be printed with different printing media, have different amounts of printing media, or different geometries. Preferably, the inked area types are arranged systematically on the substrate, or in a manner that periodically repeats along at least one spatial direction, preferably along two spatial directions, or form a repeating upper-level pattern. Particularly preferably, the electronic paper or EPD has at least three inked area types, namely red, green, and blue. Furthermore, for one or more of these colors, inked area types of different shapes and / or sizes can be given, thereby correspondingly increasing the total number of inked area types to be printed on the substrate. Therefore, a plurality of ink-receiving area grids are provided on the substrate surface in a staggered manner, wherein the plurality of ink-receiving area grids are preferably arranged in the gaps between other ink-receiving area grids, particularly in such a manner that the ink-receiving areas of different ink-receiving area grids are arranged in a manner that repeats periodically along the substrate surface. Particularly preferably, a plurality of ink-receiving area grids are provided with slightly staggered origins, wherein the ink-receiving area grids are particularly preferably formed in the same manner as each other.

[0020] The ink-receiving areas of the substrate are preferably arranged in an ink-receiving area grid consisting of rows and columns of ink-receiving areas. The rows and columns of ink-receiving areas are particularly preferably positioned at fixed angles to each other and / or in a constant mutual arrangement across the entire substrate surface. More particularly preferably, the rows and columns of ink-receiving areas are perpendicular to each other and / or arranged in a rectangular matrix. Although the rows and columns of ink-receiving areas are preferably identical, their dimensions and / or layout may differ, or the ink-receiving areas may be randomly placed within the ink-receiving area grid, in which case it is a pseudo-random grid. To align the substrate relative to the printing apparatus or to the nozzle control device, the substrate may also have alignment features, which are preferably detected by optical or other sensing methods.

[0021] A single pattern refers to a single printed surface, wherein each single pattern consists of at least two droplets of printing medium or ink printed using one or more printhead nozzles. Preferably, each single pattern is printed within exactly one inked area, or each inked area contains exactly one single pattern. Particularly preferably, for a given type of inked area, all single patterns are identical to each other, and even more particularly preferably, they are printed using the same layout and / or number of printing medium droplets.

[0022] To avoid optical interference and anomalies in the printing results, according to the method of the present invention, droplets are printed on the substrate in a manner that counteracts the mutual influence of droplets within the single pattern, preferably within each of the single patterns. The mutual influence of droplets generally refers to the fact that the characteristics of droplets arriving on the substrate are at least altered due to pre-placed and / or simultaneously arriving droplets compared to the characteristics of isolated droplets, thus changing the visual impression of the printing result.

[0023] An example of this effect is the merging of two droplets on a substrate, which typically reduces the size of the covered area while simultaneously increasing its intensity. The effect can also occur when droplets that have already arrived in adjacent areas cause the area to be printed on the substrate to be wetted by a portion of the arriving droplet or by components of the arriving droplet (such as its solvent). However, avoiding mutual influence does not, in principle, mean eliminating droplet contact on the substrate; placing droplets in a non-contact or spaced-apart manner is merely one feasible implementation. More precisely, mutual influence can also be avoided by ensuring that the droplet influence is symmetrical, i.e., all droplets in a single pattern influence each other to an equal degree, and wherein, for example, the droplets are printed onto the substrate at the same distance from each other and / or simultaneously.

[0024] Within at least a portion of a single pattern, preferably within each of the single patterns, mutual interference can be reduced or even prevented, particularly by spatial and / or temporal control of at least one printhead, especially the nozzles of each printhead used for printing droplets. This control is particularly preferred by placing droplets within the single pattern on the substrate while minimizing interaction, and especially by achieving non-interacting droplet placement. Within the scope of this spatial and / or temporal control, the order, timing, and / or spatial position of droplet placement can be changed or adjusted.

[0025] In order to achieve both particularly fast printing and particularly precise droplet positioning, a preferred embodiment of the method for printing substrate according to the invention involves printing all droplets of a single pattern and / or all droplets in the area below the print head during exactly one relative movement between the print head and the substrate, particularly during exactly one pass.

[0026] In an advantageous improvement to the method of printing a substrate according to the present invention, all droplets of a single pattern are printed within a time interval of less than 100 ms, preferably less than 50 ms, particularly preferably less than 10 ms, and even more particularly preferably less than 1 ms, thereby particularly easily preventing mutual interference caused by droplets extending into the areas of subsequent droplets arriving on the substrate. All droplets arrive on the substrate nearly simultaneously, so the state of the substrate is the same for all droplets. Furthermore, for two droplets printed adjacent to each other in a single pattern, whenever an interaction occurs, one droplet affects the other to an equal degree, so the two droplets ultimately result in the same visual impression of the printed substrate. Furthermore, it is preferable that printing from all the side-by-side printhead nozzles to a single inking area is performed simultaneously, and / or, all droplets of a single pattern are printed sequentially and / or in this order along the direction of movement of the printhead relative to the substrate.

[0027] In a particularly preferred embodiment of the method according to the invention, all droplets of a single pattern are placed on a substrate in a manner such that the ink of each droplet does not come into contact with the ink of all other droplets on the substrate (especially those of the corresponding single pattern), thereby preventing the merging of several droplets. Preferably, the droplet volume and / or the distance between adjacent printed droplets are selected in a manner that minimizes the distance between droplets on the substrate, thereby achieving good color coverage. Regarding this non-contact placement, the droplets can be applied in any order and / or at any time.

[0028] To effectively counteract the interaction of droplets, a preferred embodiment of the method according to the invention involves printing all droplets of all single patterns of a single inking zone type under the printhead in a single pass, and / or, during exactly one relative movement of the printhead and the substrate, particularly during exactly one pass, printing a single pattern of a single inking zone type by only one printhead or by only one of several printheads, wherein, preferably, each of the single patterns is printed completely simultaneously, or all droplets of the corresponding single pattern are printed. More particularly preferably, only one pass is performed for each inking zone type, or all single patterns of a specific inking zone type are printed during exactly one pass. Furthermore preferably, during a specific pass, droplets are not printed into a single pattern of another inking zone type located under the printhead.

[0029] To improve the positional resolution beyond the original positional resolution of the printhead, it is preferable to print each individual pattern and / or each movement trajectory of the printhead relative to the substrate using k staggered passes, wherein each pass causes the printhead and the substrate surface to be offset from each other by a certain lateral staggered distance. Here, a is the minimum distance between the nozzle trajectories of two nozzles with respect to the original printing resolution, or the distance a between two adjacent printing head nozzles of the print head. In addition, it is particularly preferred to select j < k. Here, j is preferably selected from the set of all non-zero natural numbers. For each traversal, the integer j can be different from each other, but it can also be the same for several traversals or for the entire printing. Therefore, the interleaving number k is used to improve the printing resolution, so an effective printing resolution of 2400 ppi can be achieved on the substrate with an original printing resolution of 600 ppi and k = 4.

[0030] In addition, in order to minimize or even completely eliminate the undesired or asymmetric interaction of the droplets of a single pattern, in an advantageous improvement of the method of the present invention, all the droplets are printed into each single pattern in an interleaving traversal with a time less than 100 ms, preferably less than 50 ms, particularly preferably less than 10 ms, and further particularly preferably less than 1 ms.

[0031] Although the substrate can in principle be any surface, the substrate is preferably a display surface and particularly preferably the surface of an electronic paper. Therefore, there is a corresponding improvement of the method of the present invention for manufacturing a color electronic paper. Among them, compared with traditional inkjet printing, such as printing graphics on paper, a special challenge is that local optical errors and irregularities are particularly likely to be manifested on the periodic pattern composed of recurring color pixels to be printed. Therefore, a particularly precise and interference-free printing result needs to be achieved within the entire printing surface range. Correspondingly, it is also very preferably that the single pattern and / or the single pattern type is the filter surface of a display, particularly the filter surface of an electronic paper. Detailed implementation mode

[0032] Several embodiments of the method of the present invention will be described in detail below.

[0033] As an example of a flexible substrate, a flexible electronic paper display with a black / white resolution of 150 ppi and a TFT pixel size of 170 μm is used to exemplarily print a single color filter dye. Among them, each color pixel should be slightly smaller than the TFT pixel size, that is, about 150 μm. Correspondingly, ink-receiving areas are provided on the substrate to accommodate the color filter dyes in a rectangular grid composed of ink-receiving area rows and ink-receiving area columns. Among them, the ink-receiving area rows extend substantially along the printing direction, and the substrate can move along the printing direction under a print head including sixteen printing head nozzles arranged in a column to print the substrate. However, the ink-receiving area rows do not need to be precisely parallel to the printing direction in principle.

[0034] In practice, unlike this greatly simplified example, instead of printing a single inking grid, several staggered inking grids are typically printed, where inking areas of a certain type are repeatedly arranged on the substrate. Typically, at least one inking area of ​​a certain inking type (e.g., a color filter) is printed into a color pixel.

[0035] However, for technical reasons, it is not always possible to fabricate a substrate surface to be printed in a way that allows the droplets to be completely absorbed immediately upon arrival at the substrate. In particular, there may be cases where droplets are arranged within a single pattern in a manner that comes into contact with droplets already printed on the substrate. In such cases, the still-wet ink and the surface stress effect of the substrate can cause several droplets within a single pattern to fuse. The exact geometry of the resulting fused droplets is largely influenced by the spatial and temporal order of the applied droplets.

[0036] This leads to an embodiment of the method according to the invention, which utilizes inkjet printing to print various schemes for printing substrates for electronic paper, wherein, by means of a printhead nozzle of at least one printhead, a single pattern consisting of at least two droplets is printed on the inking area of ​​the flexible substrate of the electronic paper. In principle, the method is operated in a certain manner, and for this purpose, particularly the at least one printhead is controlled in a certain manner, such that droplets are printed within each single pattern in a way that minimizes the mutual influence of droplets on the substrate within each single pattern.

[0037] According to a preferred embodiment of the method that minimizes the interaction of droplets, a number of individual patterns are first selected, and then these individual patterns are printed completely during a single pass of the printhead or during a single relative movement of the printhead relative to the substrate. All droplets of a single pattern are printed within a maximum of 2 ms.

[0038] In a specific embodiment of the method that minimizes the interaction of droplets, all droplets of each individual pattern or each individual pattern of a particular individual pattern type (e.g., red pixels) are printed during exactly one relative movement of the printhead relative to the substrate, thereby printing all droplets of a single pattern in a very fast timing sequence on the one hand, and in a defined, repeating order for all individual patterns on the other.

[0039] Furthermore, it is preferable to place droplets of a single pattern in a manner that prevents them from directly contacting another droplet at least upon reaching the substrate surface. Particularly preferred is to place the droplets in a manner that prevents them from contacting each other at all, or to place them into contact on the substrate very late, just before drying.

[0040] In one feasible embodiment of the printing method that minimizes the mutual influence of droplets, when all droplets printing a single pattern are completely printed during the same transition or relative movement, a substantially uniformly printed single pattern, particularly of the same ink area type, such as a corresponding color filter surface, is achieved within the substrate area. For this purpose, the distance between the printhead nozzles is preferably equal to the desired distance of the droplets on the substrate surface, corresponding to the desired lateral printing resolution. Alternatively, a printhead comprising several rows of sequentially arranged and laterally staggered printhead nozzles can be used, thereby achieving a higher printing resolution than the original resolution of a single row of printhead nozzles.

[0041] As an alternative or supplementary approach, after the first relative movement through the inking zone, the printhead can be moved laterally, and in another relative movement, droplets can be printed into the gaps between the already printed droplets. To prevent undesirable interactions between droplets in this case as well, all droplets released during the first relative movement of the printhead relative to the substrate are released into a single pattern almost simultaneously (typically <1–2 ms), and after about 0.5 s to 2 s, the next relative movement is performed, and droplets are applied to the single pattern accordingly.

[0042] For example, an electronic paper display consists of square black / white pixels of 84.5 micrometers in size, and it is desirable to print red, green, and blue filter inks onto this display. Therefore, in the simplest case, three ink application zones are needed, one for red, one for blue, and one for green. To improve placement accuracy, it might be desirable to apply ink to the substrate surface in n = 3 shifts (i.e., relative movements), thereby increasing the printhead's original resolution, for example, 1200 dpi, to 3 × 1200 = 3600 dpi.

Claims

1. A method for printing on a substrate using inkjet printing, wherein... - An ink application area is defined on the substrate, and - Using at least one printhead nozzle, a single pattern consisting of at least two droplets is printed onto the inked area, wherein -During the printing process, the nozzle of the print head moves relative to the surface of the substrate. Its features are, - Print droplets within at least a portion of the single pattern in a manner that counteracts the mutual influence of droplets within the single pattern on the substrate.

2. The method for printing on a substrate according to claim 1, characterized in that, Spatially and / or temporally controlling the at least one printhead for printing droplets within at least a portion of the single pattern, thereby enabling non-interacting droplet placement within the single pattern on the substrate.

3. The method for printing on a substrate according to claim 1 or 2, characterized in that, During exactly one relative movement between the print head and the substrate, all droplets of a single pattern and / or all droplets in the area below the print head are printed.

4. The method for printing on a substrate according to claim 1 or 2, characterized in that, Print all droplets of a single pattern within a time interval of less than 100ms.

5. The method for printing on a substrate according to claim 1 or 2, characterized in that, All droplets of a single pattern are placed on the substrate in a certain manner, such that the ink of each droplet does not come into contact with the ink of all other droplets on the substrate, thereby preventing the merging of several droplets.

6. The method for printing on a substrate according to claim 1 or 2, characterized in that, - To print all droplets of a single pattern of a single inking zone type under the print head in a single pass, and / or - During exactly one relative movement between the print head and the substrate, a single pattern of a single inking area type is printed using only one print head or by a single one of several print heads, wherein - Simultaneously print all droplets of each or all corresponding single patterns in the single pattern.

7. The method for printing on a substrate according to claim 1 or 2, characterized in that, To improve the positional resolution beyond the original positional resolution of the printhead, each individual pattern and / or each movement trajectory of the printhead relative to the substrate is printed using k staggered passes, wherein in each of the passes, the printhead and the surface of the substrate are offset from each other by a certain lateral staggered distance. Where a is the minimum distance between the two nozzle trajectories, and j <k。 8. The method for printing on a substrate according to claim 1 or 2, characterized in that, Imprint all droplets into each individual pattern during staggered crossings with a time of less than 100ms.

9. The method for printing on a substrate according to claim 1 or 2, characterized in that, The substrate is the surface of the display.

10. The method for printing on a substrate according to claim 1 or 2, characterized in that, The single pattern and / or the single pattern type is the filter surface of the display.

11. The method for printing on a substrate according to claim 1 or 2, characterized in that, Droplets are printed within each of a single pattern.

12. The method for printing on a substrate according to claim 1 or 2, characterized in that, During exactly one pass of the print head and the substrate, all droplets of a single pattern and / or all droplets in the area below the print head are printed.

13. The method for printing on a substrate according to claim 1 or 2, characterized in that, Print all droplets of a single pattern within a time interval of less than 50ms.

14. The method for printing on a substrate according to claim 1 or 2, characterized in that, Print all droplets of a single pattern within a time interval of less than 10ms.

15. The method for printing on a substrate according to claim 1 or 2, characterized in that, Print all droplets of a single pattern within a time interval of less than 1 ms.

16. The method for printing on a substrate according to claim 1 or 2, characterized in that, All droplets of a single pattern are placed on the substrate in a manner such that the ink of each droplet does not come into contact with the ink of all other droplets of the corresponding single pattern located on the substrate, thereby preventing the merging of several droplets.

17. The method for printing on a substrate according to claim 6, characterized in that, During exactly one pass of the print head and the substrate, a single pattern of a single inking area type is printed by only one print head or by a single one of several print heads.

18. The method for printing on a substrate according to claim 1 or 2, characterized in that, Imprint all droplets into each single pattern in an interlaced crossing time of less than 50ms.

19. The method for printing on a substrate according to claim 1 or 2, characterized in that, Imprint all droplets into each single pattern in an interlaced crossing time of less than 10 ms.

20. The method for printing on a substrate according to claim 1 or 2, characterized in that, Imprint all droplets into each single pattern in an interlaced crossing time of less than 1 ms.

21. The method for printing on a substrate according to claim 1 or 2, characterized in that, The substrate is the surface of electronic paper.

22. The method for printing on a substrate according to claim 1 or 2, characterized in that, The single pattern and / or the single pattern type is the filter surface of the electronic paper.

Images