Method for creating printing plates

Abstract

A method for producing a printing plate, comprising: selecting a digital image (100, IMG nonimgpix ) having a continuous area of image pixels (107, A imgpix ) surrounded by a continuous area of non-image pixels (105, A sel ); determining a boundary (200, B) of the continuous area (107, A imgpix ); according to the boundary (200, B) and within the continuous area of image pixels (107, A imgpix ), determining a first border area (207, BA1); and according to the boundary (200, B) and within the continuous area of non-image pixels (105, A nonimgpix ), determining a second border area (205, BA2); selecting N consecutive clusters (CL sel、1..N ) from the first border area (207, BA1), and moving each consecutive cluster (CL sel、1..N , i) of the N consecutive clusters (CL sel ) to the second border area (205, BA2) to adapt the selected digital image (100, IMG sel ); and forming an image of the adapted digital image (IMG adp ) on a printing plate material to form the printing plate.

Description

[Technical Field]

[0001] The present invention relates to the technology of printing plates, in which print quality is improved by fitting a digital binary image onto the printing plate material before image formation. [Background technology]

[0002] In the field of printing plate technology, digital images are formed on printing plate materials such as lithographic printing plates.

[0003] The use of printing plates and the process of forming printing plates by creating images from digital images onto printing plates are well-known as part of conventional printing technology. Helmut Kipphan's "Handbook of Print Media" (ISBN 3-540-67326-1 - Springer-Verlag Berlin Heidelberg New York) particularly discusses this in Chapter 1.3 "Printing technologies" and Chapter 2 "Printing Technologies with Permanent In "Printing Master," several types of the aforementioned conventional printing techniques are disclosed. Image formation is sometimes also called image-wise exposure.

[0004] Examples of how lithographic printing plates are produced (by infrared light) and how digital images are formed on said printing plates are disclosed in Patent Document 1 (AGFA NV).

[0005] Another type of printing plate is a flexographic printing plate. Examples of how such printing plates are made, or how digital images are formed on such printing plates by laser engraving, are disclosed in Patent Document 2 (AGFA NV). In flexographic printing, the image-forming printing plate is primarily a photopolymer plate having a convex or concave pattern corresponding to the desired halftone. When ink is applied to the plate and transferred to the substrate, it generates dots of different sizes at various depths of the plate, which then creates the illusion of continuous tone.

[0006] A digital image formed on a printing plate contains information that needs to be printed on the printing medium with ink. The digital image includes image pixels and non-image pixels that determine where on the printing medium the ink should be applied when the printing plate is used. For example, a pixel in a digital image may have a value of 1 if it is an image pixel and a value of 0 if it is a non-image pixel.

[0007] Conventional printing techniques simulate digital continuous tone images, such as photographs, on a print medium. In this process, the digital continuous tone image is first halftoned using halftone technology, generating a halftone image containing dots of varying sizes and / or spacing, which is then formed to simulate the digital continuous tone image. These formed dots are either image pixels or non-image pixels. This allows the eye to blend the dots to perceive the desired hue, enabling the printing of the image using only a limited number of ink colors. An example of halftoning technology is disclosed in Patent Document 3 (AGFA NV), where spiral halftone dots with image pixels are formed. Furthermore, Chapter 1.4.3 "Halftone Process / Screening" of Helmut Kipphan's "Handbook of Print Media" discloses other halftoning techniques.

[0008] Half-toning technology is typically performed in a raster image processor (RIP) or prepress workflow, such as Prinect Workflow (trademark) of manufacturer Heidelberg Durckmaschinen Aktiengesellschaft or Apogee (trademark) of manufacturer ECO3, where a file in a page description language is converted into a digital continuous tone image and a halftone image, and the halftone image is transferred to an imaging system to create a printing plate from a printing plate material such as an imagesetter.

[0009] To ensure the simulation of a continuous tone image, the continuous tone image is linearized (also called calibrated) before or during half-toning. This is usually done by a dot gain (correction) curve that defines the percentage to be used on the printing plate for each desired percentage on the printing press. That is, linearization serves to control conventional printing technology so that the printed color operates linearly with respect to the input color of the continuous tone image.

[0010] At the boundary of the printed continuous area of the image pixels of a digital image, there is a local density difference with respect to the center of the printed continuous area of the image pixels, and / or printing anomalies such as ghosting or halo printing have been found. The printing artifacts depend on the printing medium and / or printing parameters used in conventional printing technology, for example, a greater pressure on the printing plate during ink transfer via an intermediate press roll or directly to the printing medium, less use of dampening water, or use of more oily ink.

[0011] Therefore, a solution with fewer of the printing artifacts and less dependence on the printing parameters and preferably not interfering with linearization is needed.

Prior Art Documents

Patent Documents

[0012] [Patent Document 1] International Publication No. 2010122042A1 Pamphlet [Patent Document 2] International Publication No. 2008074796A1 Pamphlet [Patent Document 3] International Publication No. 2019081493A1 Pamphlet [Overview of the project]

[0013] The object of the present invention is to provide a method for producing a printing plate that has excellent printing properties and overcomes the aforementioned printing artifacts. The present invention also ensures that the linearization of the continuous tone image to be printed, performed before or during halftoning, is stable or remains the same.

[0014] This objective is achieved by the method for producing a printing plate as defined in claim 1.

[0015] Another aspect of the present invention is a printing plate produced according to the method described above.

[0016] Other features, elements, processes, properties, and advantages of the present invention will become more apparent from the drawings of preferred embodiments of the invention and the following detailed description. Specific embodiments of the invention are also defined in the dependent claims. [Brief explanation of the drawing]

[0017] [Figure 1] Several steps of a preferred embodiment are shown. First, a digital image (100, IMGsel) is selected (400) having a continuous region of image pixels (107, Aimgpix) surrounded by a continuous region of non-image pixels (105, Anonimgpix). [Figure 2]An example of such a digital image (100, IMGsel) is shown. Boundaries; a first border area and a second border area are determined from the digital image (401). The results of the determination are shown in Figures 3 and 4. The next step is to fit the digital image (100, IMGsel) by moving image pixels from the first border area (207, BA1) to the second border area (205, BA2), as shown in Figures 5, 6, 7 and 8 (402), after which the fitted digital image (300, IMGadp) is image-formed on the printing plate (403). [Figure 3] The determined boundary (200, B) of the contiguous region (107, Aimgpix) of the image pixels shown in Figure 1 is shown. [Figure 4] Figure 1 shows the selected digital image (100, IMGsel) containing the determined boundary (200, B), the first border area (207, BA1) between the inner dark line and the boundary (200, B), and the second border area (205, BA2) between the outer dark line and the boundary (200, B). [Figure 5] A preferred embodiment of the process is shown, in which a 1x1 continuous cluster (CLsel, 1..N) is moved from a first border region (207, BA1) to a second border region (205, BA2) (indicated by a black arrow). [Figure 6] This is the same as Figure 4, but it shows a process using a different shape of continuous cluster (CLsel, 1..N). [Figure 7] This is the same as Figure 5, but it shows the process in which a continuous cluster (CLsel, 1..N) within the first border area (207, BA1) is moved to the second border area (205, BA2) and divided into multiple parts. [Figure 8] The central region (209) is shown to undergo an additional process in which non-image pixels are converted according to a regular line pattern. [Modes for carrying out the invention]

[0018] One aspect of the present invention for resolving the aforementioned printing artifacts is: a) Selecting (401) a digital image (100, IMG nonimgpix ) having a continuous area of image pixels (107, A imgpix ) surrounded by a continuous area of non-image pixels (105, A sel ); b) Determining (402) the boundary (200, B) of the continuous area (107, A imgpix ); - A first border area (207, BA1) that is along the boundary (200, B) and within the continuous area of image pixels (107, A imgpix ); and - A second border area (205, BA2) that is along the boundary (200, B) and within the continuous area of non-image pixels (105, A nonimgpix ); Determining the process, c) Selecting N consecutive clusters (CL sel、1..N ) from the first border area (207, BA1), and moving one of the N consecutive clusters (CL sel、1..N ), preferably each consecutive cluster (CL sel , i) to the second border area (205, BA2) to adapt the selected digital image (100, IMG sel ) (403: Figures 5; Figures 6; Figures 7; Figures 8); d) Forming an image of the adapted digital image (300, IMG adp ) on a printing plate material (404) to form the printing plate A method for producing a printing plate including the process. Here, N is a positive integer other than zero. The process is shown in Figure 1.

[0019] Therefore, in this aspect, at a first position within the first border area (207, BA1), one or more image pixels of the first border area (207, BA1) are moved to the second border - area (205, BA2). At the first position, one or more image pixels become non-image pixels, and conversely, one or more non-image pixels become image pixels within the second border area (205, BA2).

[0020] Movement at the boundary (200, B) results in a contiguous area of ​​image pixels (107, A imgpix ) is a contiguous area of ​​non-image pixels (105, A nonimgpix It is smoothed out towards (). The number of image pixels is 300 for a digital image (IMG adp It remains the same after the conformance. Contiguous area of ​​image pixels (107, A imgpix ) and the contiguous area of ​​non-image pixels (105, A nonimgpix Other border areas within the specified area may also be determined.

[0021] Furthermore, due to the movement at the boundary, the thickness of the ink layer has an advantageous effect, which is at the boundary (200, B) and in the continuous area (107, A) during printing. imgpix The ink accumulation formed within the first border area (207, BA1) has the opportunity to fill the non-image pixels formed within the first border area, thereby making the ink thickness thinner and reducing the need for drying capacity depending on the conventional printing technology used.

[0022] Preferably, the printing plate material is for lithographic printing. More preferably, the printing plate material is for flexographic printing, where ghost printing and halo printing are more difficult to resolve.

[0023] One or more consecutive clusters (CL) sel、1..N The selected positions are preferably distributed within the first border area (207, BA1), and preferably uniformly distributed.

[0024] In a preferred embodiment, when the printing plate is used in a particular conventional printing technique, the printing direction is known. The printing plate material is mainly rectangular, and therefore the sides of the printing plate material are parallel to the printing direction when mounted in a system according to the conventional printing technique. Thus, one or more selected continuous clusters (CL) sel、1..NIt is preferable that the ) be positioned along a direction substantially perpendicular to the printing direction, in particular to avoid halo printing and ghost printing.

[0025] In particular when lithographic or flexographic printing technology is used, the continuous area of ​​printed image pixels (107, A imgpix To obtain a more uniform print density in ), N consecutive clusters (CL) are used. sel、1..N The ) are preferably selected according to a predetermined pattern, preferably a regular pattern such as tiled rectangles, ellipses or rhombuses, and / or each of the N consecutive clusters has the same size and shape, e.g., ellipses, rectangles or rhombuses. If determined in addition to the first and second border areas (207, BA1, 205, BA2), other border areas may use different patterns or other shapes / sizes.

[0026] printing plate material In a preferred embodiment, the printing plate material is for lithographic printing or flexographic printing.

[0027] Printing plates are a well-known technical means in the fields of flexographic and planar printing, in which a digital image is formed by chemical and / or mechanical reactions to form a printing plate, which is then used in a planar or flexographic printing system such as a printing press. Image formation is preferably performed directly on the printing plate using a printing plate setter, but may be performed indirectly by exposing the printing plate to light via an intermediate film or digital mask panel, where the film or digital mask panel includes a representation of a digital image. The intermediate film may be produced by an image setter. Printing plate Examples of setters include the Avalon® series from manufacturer ECO3 or the FLEXCEL NX Wide 5080 System from manufacturer MIRACLON. An example of an image setter is the Avantra® series from manufacturer ECO3. An example of the digital mask panel is disclosed in European Patent No. 3608721A1 (AGFA NV). An example of image formation on flexographic printing plates is disclosed in European Patent No. 2539667A1 (MACDERMID PRINTING SOLUTIONS). An example of a process-free printing plate is Eclipse® from manufacturer ECO3.

[0028] Directly on plate is also called computer-to-plate (CTP). Inkjet technology may be used here, and this is also called inkjet CTP. An example of inkjet CTP is disclosed in European Patent No. 2097247A2 (AGFA NV).

[0029] Image formation can sometimes occur on the printing press itself; this is called Direct-On-Press (DOP).

[0030] Digital images Digital images are obtained using appropriate commercially available hardware, such as scanning photographs or taking images with a digital camera, and / or commercially available software, such as Adobe Photoshop®, for manipulating and creating digital images. Digital images may include logos, text, photographs, diagrams, or combinations of logos, text, diagrams, and / or photographs.

[0031] A digital image is a two-dimensional digital image having specific dimensions (width and height) and containing multiple pixels. Pixels are also called picture elements. Most digital images are organized into a square grid, but rectangular or hexagonal grids are also possible. Each of the multiple pixels has a specific value representing its intensity. The resolution (horizontal, vertical, hexagonal) of a digital image specifies the number of pixels in 1 cm or 1 inch. Preferably, the (vertical and horizontal) resolution of a digital image is 900 to 15,000 pixels per inch. For example, recently, printing plate setters capable of outputting printing plates at 9,600 pixels per inch are used in security printing (extremely fine lines, extremely small letters, etc.).

[0032] When only two values ​​exist that can represent the aforementioned intensity, the digital image is also called a binary digital image.

[0033] The content of a digital image may be defined by a raster graphics format, such as Portable Network Graphics (PNG), Tagged Image File Format (TIFF), Adobe Photoshop Document (PSD), or Joint Photographic Experts Group (JPEG), or a bitmap (BMP).

[0034] Digital images may be stored and / or loaded into a computer's memory as one or more files.

[0035] Digital images can be fitted by moving pixels from one position to another, which is a common feature in digital image processing, especially digital image editing. For example, in Adobe Photoshop® Version 21.0.1, the operator can move one or more pixels to a specific position using the “Rectangular Marquee Tool” and the “Move Tool”. Once selected, the selected pixels can be moved to other locations by drag and drop. In fact, after moving, one or more pixels at a particular location become non-image pixels (appearing white), while at other locations, the pixel values ​​are overwritten by the values ​​of the selected pixels.

[0036] Preferably, the digital image is linearized to control conventional printing techniques so that it operates linearly with respect to the input color of a continuous tone image, especially when dot gain effects are present. Linearization can be achieved by tone mapping, a well-known method in digital image processing, where measurements of a printed test target are used. One advantage of this and preferred embodiment is that the number of image pixels remains the same, so the digital image (100, IMG sel The linearization of the digital image (300, IMG adp ) remains substantially the same after compliance.

[0037] In a preferred embodiment, the values ​​of the moved image pixels are preferably adapted to a higher luminosity, but remain image pixels. Such adaptation is necessary to drive the printing plate setter or image setter. At the positions of the moved image pixels with adapted values, the chemical and / or mechanical reactions during plate formation should be less than those of the unmoved image pixels, for example, the chemical and / or mechanical reactions should be less. Less chemical and / or mechanical reaction may result in a lower height after image formation of the printing plate material for flexographic printing.

[0038] a) Halftone image The digital image is preferably a halftone image, also known as a raster image. The halftone image is suitable for reproducing a continuous tone image, that is, it creates the illusion of a continuous tone image on a printed copy.

[0039] The halftone image preferably includes halftone dots, more preferably AM dots (amplitude-modulated dots) and / or XM dots (cross-modulated dots) and / or semi-randomly located dots, such as (clustered) FM dots (frequency-modulated dots) and / or DM dots (digital-modulated dots), selected from the list.

[0040] Halftone dots may be arranged according to a regular tile pattern, or they may be placed locally in a semi-random manner.

[0041] b) Contiguous region of (non)image pixels A contiguous region of image pixels (107) is a region of image pixels connected to form the contiguous region. Non-image pixels are not part of such a contiguous region of image pixels.

[0042] A contiguous region of non-image pixels (105) is a region of non-image pixels connected to form the contiguous region. Image pixels are not part of such a contiguous region of non-image pixels.

[0043] In a preferred embodiment, a continuous area of ​​non-image pixels (105, A nonimgpix ) has two or more image pixels, more preferably a minimum of nine non-image pixels.

[0044] Contiguous area of ​​non-image pixels (105, A nonimgpix The number of non-image pixels within ) is preferably a continuous area of ​​image pixels (107, A imgpix It is greater than the number of image pixels within the parentheses.

[0045] Selected N consecutive clusters (CL) sel、1..N The total number of image pixels within ) is the number of consecutive image pixels (107, A imgpix It is smaller than the number of image pixels within the parentheses.

[0046] Selected digital images (100, IMG sel) is a halftone image containing multiple halftone dots, and the selected image pixels are a contiguous area (107, A imgpix ) may be one of the aforementioned halftone dots. The shape of the halftone dot may be circular, elliptical, rectangular, diamond, rhombus, spiral, one ring, or two rings. The shape affects the overall transition and ripple patterns of the printed digital image, as well as other visual artifacts. In a preferred embodiment, a continuous area of ​​image pixels (107, A imgpix ) has two or more image pixels, more preferably a minimum of nine image pixels. In particular, when a contiguous area of ​​image pixels is a halftone dot in the highlight area, it has been found that it is better to preserve the halftone dot rather than move the image pixels to a second border area (205, BA2).

[0047] c) Boundary (200, B) In halftone image formation, the boundary refers to the transition between two different tone levels within the halftone image.

[0048] In image processing, there are several known image boundary detection methods, including edge detection (e.g., Canny edge detection); thresholding, which involves setting a threshold and then highlighting all pixels in the image that exceed that value. This can create binary boundaries that separate regions of an image; morphological operations, e.g., erosion; and contour detection, which involves identifying the boundaries of objects in an image by detecting curves that connect points of similar color or intensity. An example of a method that can determine boundaries is disclosed in S. Anam, E. Uchino, N. Suetake, Image Boundary Detection Using the Modified Level Set Method and a Diffusion Filter, Procedia Computer Science, Volume 22, 2013, Pages 192-200, ISSN 1877-0509.

[0049] Digital image (100, IMG sel ) is preferably a binary digital image if it is suitable for image formation on a printing plate material to form a printing plate. To determine the boundaries, the digital image may be converted to an 8-bit grayscale image, and then a convolutional filter may be applied with a kernel size equal to a given border. The result is an image with pixels that were originally 255 as a value and, after filtering, are not equal to 255. They define the boundaries of contiguous regions of image pixels.

[0050] In a preferred embodiment, the convolutional filter uses a square or circular convolutional mask, and more preferably, all values ​​in the kernel are 1.

[0051] d) Border zone (205, BA1, 207, BA2) In the context of image processing, the border region of a contiguous area of ​​(non-)image pixels refers to the pixels or region surrounding the boundary of the contiguous area. The shape of the boundary is (more or less) similar to the shape of the border region.

[0052] c) By using convolution filtering as described in the Boundaries chapter, and by fitting the kernel size to, for example, the requested border size range × 2 + 1, (non)image pic Border regions at the boundaries of contiguous cell regions can also be determined. By using two convolutions of different kernel sizes, border regions with a specific selected thickness (sometimes called width or depth) can be determined within contiguous regions of (non-)image pixels.

[0053] One example of a method for defining border areas BA1 and BA2 close to the boundary can be achieved as follows: Converts a binary image to an 8-bit grayscale image. A convolution filter is applied with a kernel size equal to (requested border range x 2 + 1) depending on the thickness of the requested border area. Before the filter is applied, all pixels have either a value of 255 (black) or 0 (white). After convolution with the filter, four types of pixels can be defined: a. Pixels that were originally 0 and are currently ≠ 0 (adjacent to a contiguous area of ​​image pixels and can be used as a second border area BA2); b. Pixels that were originally 0 and are currently 0 (part of a contiguous area of ​​non-image pixels); c. Pixels (boundaries) that were originally 255 and are currently ≠255; d. Pixels that were originally 255 and are currently 255 (within a contiguous region of image pixels). A range adjacent to a contiguous area of ​​image pixels (one or more contiguous clusters (CL)) sel、1..N If the area to be moved differs from the requested border range, two convolutions are required using filters with different kernel sizes. The convolution mask can be either square or circular. All values ​​inside the kernel are 1.

[0054] The border area preferably has (more or less) the same distance (=same thickness / same width / same depth) between its edges, and the edges follow the boundary.

[0055] In a preferred embodiment, the thickness (also called width or depth) of the border region (205, BA2) is more preferably equal to or greater than the thickness (also called width or depth) of the first border region (207, BA1) when the contiguous region of non-image pixels is larger than the contiguous region of image pixels.

[0056] e) Continuous clusters In this manner, selected continuous clusters (CL) sel、i) comprises one or more image pixels, preferably up to 32 image pixels, more preferably up to 16 image pixels, and most preferably up to 8 image pixels. Fewer selected consecutive clusters are used to address print quality issues and selected digital images (100, IMG sel ) is preferable to avoid loss of details.

[0057] The one or more selected contiguous clusters (CL) sel Each of i) has a specific size, also called dimensions and shape. The size and shape may be defined by a selected pattern, for example, a 2x2 pattern. One or more selected continuous clusters (CL) sel、1..N It is preferable that all of them are the same size and shape, where N is a positive integer greater than zero.

[0058] The total number of image pixels in one or more selected consecutive clusters is preferably less than 75% of the total number of image pixels in the first border area (207, BA1).

[0059] Preferably, one or more selected consecutive clusters (CL) sel、1..N If two or more consecutive clusters are selected, they are spaced apart from each other and more preferably uniformly distributed within the first border area (207, BA1). s el、1..N ) is the one or more consecutive clusters (CL sel、1..N The location of the continuous cluster (CL) may be determined by using an image mask placed on the first border area (207, BA1). sel、1..N ) may be selected within the first border area (207, BA1) according to a pattern such as a checkerboard pattern, or, for example, pseudo-randomly using a blue noise mask within the first border area (207, BA1).

[0060] Preferably, one or more selected consecutive clusters (CL) sel、1..N) is separated from the boundary.

[0061] Preferably, a moved continuous cluster (CL) mov、1..N These clusters are spaced apart from each other and more preferably uniformly distributed within a second border area (205, BA2). mov、1..N These are preferably distributed pseudo-randomly within the second border area (205, BA2).

[0062] In a preferred embodiment (Figure 7), a selected continuous cluster (CL) having two or more image pixels is provided. sel Each of the, i) at least one, preferably selected, continuous cluster is, - Moved to the second border area (205, BA2) without being divided; or - Divided into multiple parts, the multiple parts are moved apart from each other into a second border area (205, BA2), more preferably, at least one of the moved parts is connected to the boundary.

[0063] In a preferred embodiment (Figure 8), a first border area (207, BA1) and a continuous area of ​​image pixels (107, A imgpix A central area (209) is determined between the center of (107, A), and a plurality of image pixels within the central area (209) that follow a predetermined regular pattern are changed to non-image pixels. The change step is performed in a large continuous area (107, A) of image pixels. imgpixTo improve the uniformity of the printing. The large continuous area of ​​image pixels preferably exceeds 50 image pixels, more preferably exceeding 200 image pixels. The regular pattern may be regularly spaced lines or dots or star shapes or spirals or any other geometric structures. Regularly spaced lines preferably have a maximum thickness of 8 pixels. The regularly spaced lines may form corners, preferably at an angle of 45 or 135 degrees with respect to the printing direction. Regularly spaced dots preferably have a maximum dimension of 8 to 8 pixels. The regularly spaced dots may also represent dashed lines. The dashed lines preferably have an angle of 45 or 135 degrees with respect to the printing direction.

[0064] Step d) of the embodiment and its preferred embodiment involve a continuous region of image pixels (107, A) having a particularly long boundary (200, B). imgpix This may include additional steps: - Select M other contiguous clusters from the first border region (207, BA1) and change the image pixels of the M other contiguous clusters to non-image pixels, thereby creating the selected digital image (100, IMG sel ) is adapted, where M is a non-zero positive integer. A long boundary means beyond 40 pixels, more preferably beyond 80 pixels.

[0065] In a preferred embodiment, one or more selected consecutive clusters (CL) 1..N Each of the consecutive clusters is moved along the axis from the center of the consecutive region of image pixels and the position of the selected consecutive cluster. The distance traveled along the axis is preferably up to 300%, more preferably up to 200%, of the distance along the axis from the position and boundary of the selected continuous cluster.

[0066] In a preferred embodiment, up to 50%, more preferably up to 20%, of the image pixels in the first border area (207, BA1) are moved to the second border area (205, BA2). [Industrial applicability]

[0067] The present invention relates to the technical field of printing plates, and therefore satisfies the requirement of industrial applicability.

Claims

1. A method for producing a printing plate, - Contiguous area of ​​non-image pixels (105, A ｎｏｎｉｍｇｐｉｘ A contiguous region of image pixels enclosed by (107, A ｉｍｇｐｉｘ ) a digital image (100, IMG ｓｅｌ Step (401) to select ); - The aforementioned continuous area (107, A ｉｍｇｐｉｘ The boundary (200, B) of the image pixels; the boundary (200, B) and the continuous area (107, A) of the image pixels. ｉｍｇｐｉｘ The first border area (207, BA) is located within ) １ ) and the continuous area of ​​non-image pixels (105, A) according to the boundary (200, B) ｎｏｎｉｍｇｐｉｘ The second border area (205, BA) is located within ) ２ (402) step of determining ) - From the first border region (207, BA １ ), select one or more continuous clusters (CL ｓｅｌ、１．．Ｎ ), and by moving at least one continuous cluster (CL ｓｅｌ、１．．Ｎ ) of the one or more selected continuous clusters (CL ｓｅｌ ) to the second border region (205, BA ２ ), adapt (403) the selected digital image (100, IMG ｓｅｌ ); - Adapted digital image (300, IMG) ａｄｐ The process of forming an image (404) on a printing plate material to form the printing plate. Methods that include...

2. One or more selected contiguous clusters (CL ｓｅｌ、１．．Ｎ The method according to claim 1, wherein the elements are spaced apart from each other.

3. Moved continuous cluster (CL) ｍｏｖ、１．．Ｎ The method according to claim 1 or 2, wherein the elements are spaced apart from each other.

4. - One or more selected contiguous clusters (CL) ｓｅｌ、１．．Ｎ The position of ) is the first border area (207, BA １ ) are uniformly distributed within; or one or more selected continuous clusters (CL ｓｅｌ、１．．Ｎ ) are selected according to a predetermined regular pattern. The method according to any one of claims 1 to 3.

5. One or more selected contiguous clusters (CL ｓｅｌ、１．．Ｎ The method according to any one of claims 1 to 4, wherein each of the members has the same size and shape.

6. One or more selected contiguous clusters (CL ｓｅｌ The method according to any one of claims 1 to 5, wherein at least one continuous cluster of , i) is connected to the boundary (200, B).

7. One or more selected contiguous clusters (CL ｓｅｌ、１．．Ｎ The method according to any one of claims 1 to 5, wherein each of the elements is spaced apart from the boundary.

8. One or more selected contiguous clusters (CL) having two or more image pixels ｓｅｌ i) at least one contiguous cluster is not divided into the second border region (205, BA ２ ) to be moved; or divided into multiple parts and the multiple parts spaced apart from each other to form a second border area (205, BA ２ The method according to any one of claims 1 to 7, wherein the object is moved to ).

9. The method according to claim 8, wherein at least one of the moved parts is connected to a boundary.

10. First border area (207, BA １ ) and a continuous area of ​​image pixels (107, A ｉｍ ｇｐｉｘ The method according to any one of claims 1 to 12, wherein a central area (209) is determined between the center of ) and a plurality of image pixels in the central area (209) that follow a predetermined regular pattern are changed to non-image pixels.

11. Step d) is the first border area (207, BA １ Select M (M>1) other consecutive clusters from ) and change the image pixels of the M other consecutive clusters to non-image pixels, thereby creating the selected digital image (100, IMG ｓｅｌ The method according to any one of claims 1 to 12, further comprising the additional step of adapting )

12. One or more selected contiguous clusters (CL １．．Ｎ Each of the consecutive clusters of ) is a consecutive region of image pixels (107, A ｉｍｇｐｉｘ The method according to any of the preceding claims, wherein the central part of the continuous cluster is moved along the axis from the center of the cluster to the position of the continuous cluster.

13. Digital image (100, IMG) ｓｅｌ ) is a halftone image having multiple halftone dots; The halftone dots of the plurality of halftone dots are in a continuous area of ​​the selected image pixels (107, A ｉｍｇｐｉｘ The method according to any of the preceding claims, wherein the multiple halftone dots are located in a regular tiled or semi-random manner.

14. Selected contiguous area of ​​image pixels (107, A ｉｍｇｐｉｘ The method according to claim 10, wherein the shape of the ring is round, elliptical, rectangular, rhombus, spiral, one ring, or two rings.

15. The method according to any one of claims 1 to 14, wherein the printing plate material is for lithographic printing or flexographic printing.

Images