METHOD AND DEVICE FOR APPLYING A PRINTING PLATE TO A PRINTING CYLINDER, METHOD FOR MANUFACTURING A PRINTING PLATE

Description

[0001] The invention relates to a method for mounting a printing plate onto a printing cylinder, a device for mounting a printing plate onto a printing cylinder, a method for producing a printing plate, a printing plate for use in a flexographic printing process and a device for trimming the edge of a printing plate.

[0002] According to prior art known to the applicant but not documented in print, the production of a printing plate, intended in particular for use in a flexographic printing process and consisting of a flexible carrier film and a printing image layer applied to the carrier film, begins with the preparation of a printing plate blank, which is generally considerably larger than the printing plate to be produced. In a structuring process, which can be carried out, for example, with a laser light source, those areas are structured that are to serve either as the printed image or as areas between the printed image in subsequent processing steps. For example, it is envisaged that the printing plate blank is provided with an opaque coating and that the structuring is carried out by removing this coating in certain areas.In a subsequent step, the printing plate blank is exposed to light, curing the areas no longer covered by the coating. The remaining areas of the printing plate blank are then removed in a later step, typically using a wet chemical process. Currently, individual printing plates are extracted from the blank by manually cutting them out using a knife. This process may leave raised markings on the printing plates, such as registration marks or edge markers, mirroring the printed image.These markings can be used in a subsequent application process for the printing plate onto a printing cylinder intended for use in a printing machine, for the correct positioning of the printing plate relative to the printing cylinder.

[0003] An example from EP 2 535 188 A1 is a mounting device for applying a printing form to a printing form carrier, comprising a receptacle for the printing form carrier and a pressing device for transmitting a pressing force to the printing form carrier that can be inserted into the receptacle, wherein the printing form to be applied to the printing form carrier is pressed onto the printing form carrier at a pressing area by a pressing device designed to carry out a pressing movement oriented transversely to the pressing axis, and wherein correction means are provided which are designed to introduce a correction force, the direction of which deviates from a direction of the pressing force, onto the printing form carrier and the printing form to be applied thereon, in order to compensate for an offset error of the printing form along the pressing axis and / or a runout error of the printing form carrier.

[0004] The object of the invention is to provide a method for applying a printing plate to a printing cylinder, a device for applying a printing plate to a printing cylinder, a method for producing a printing plate, a printing plate for use in a flexographic printing process and a device for trimming the edges of a printing plate, with which precise positioning of the printing plate on a printing form carrier or printing cylinder can be ensured even when the printed image covers the surface of the printing plate at least almost completely.

[0005] This problem is solved according to a first aspect of the invention for a method for applying a printing plate to a printing cylinder by the following steps: providing a printing cylinder to a printing cylinder receptacle which is rotatably mounted about a printing cylinder axis on a machine frame, placing a leading edge of the printing plate on the printing cylinder and initiating a rotational movement on the printing cylinder in order to apply the printing plate to an outer surface of the printing cylinder during a rotational movement of the printing cylinder about the printing cylinder axis, wherein the printing plate is aligned during the application process by means of a positioning device.which is designed for precise positioning of the printing plate relative to the printing cylinder mount and which comprises a detection device for detecting a positioning geometry of the printing plate to be aligned transversely to the printing cylinder axis as well as adjustment means for a lateral position adjustment of a printing plate section, characterized in that the detection device detects a cut edge of the printing plate aligned transversely to the printing cylinder axis.

[0006] In such a mounting process, it can be assumed that the printing cylinder is at least partially coated with a self-adhesive layer, for example, in the form of double-sided adhesive tape, and that the printing plate, made of a rubber-elastic material, is wound onto the printing cylinder in a winding process. For this purpose, it may be provided that the printing plate, with its precisely trimmed edge relative to the printed image, is first aligned with the printing cylinder axis using a stop rail oriented transversely to the printing cylinder axis, such that the printed image is aligned with the printing cylinder with a minimal angular error before the mounting process is carried out.Subsequently, without changing the orientation of the printing plate, a leading edge of the printing plate, aligned at least substantially parallel to the printing cylinder axis, is brought into contact with the printing cylinder and thus adheres to the self-adhesive layer of the printing cylinder. The printing cylinder then rotates, winding the entire printing plate onto the cylinder.During this winding process, the cutting edge of the printing plate is continuously scanned, particularly in an area immediately before the printing plate hits the surface of the printing cylinder, using the detection device, which can be designed for contactless or contactless detection of the cutting edge of the printing plate, to check whether the cutting edge of the printing plate is straight or whether a deviation in straightness of the cutting edge occurs due to reaction forces during the winding process.If this is the case, the adjustment means, designed for lateral position adjustment of the portion of the printing plate not yet fixed to the printing cylinder, can be used to correct the alignment of the cutting edge. This ensures that the cutting edge of the printing plate is precisely aligned with the printing cylinder once the printing plate is fully mounted on it. Preferably, the cutting edge of the printing plate, after being mounted on the printing cylinder, is arranged entirely in a plane perpendicular to the printing cylinder axis.

[0007] In an advantageous further development of the method, it is provided that the cutting edge of the printing plate is trimmed before the printing plate is applied to the printing cylinder, depending on a positioning geometry formed on the printing plate, with such accuracy that the cutting edge lies within a tolerance interval of less than 50 micrometers, in particular less than 30 micrometers, relative to the printed image.

[0008] According to a further aspect of the invention, the object of the invention is achieved by a device for applying a printing plate to a printing cylinder. For this purpose, the device comprises a machine frame on which a printing cylinder receptacle is rotatably mounted about a printing cylinder axis, and a positioning device designed for the precise positioning of a printing plate relative to the printing cylinder receptacle. The positioning device comprises at least one detection device for detecting a positioning geometry of a printing plate to be aligned transversely to the printing cylinder axis, as well as adjustment means for lateral position adjustment of a section of the printing plate. The detection device is designed for scanning the cut edge of the printing plate, in particular contactless or with contact.

[0009] The object of the invention is achieved according to a further aspect of the invention for a method for producing a printing plate by the following steps: providing a printing plate blank, comprising a flexible carrier film and a printing image layer applied to the carrier film, to a structuring device; structuring a printing image into the printing image layer with the structuring device; creating a positioning geometry at at least one edge region of the printing image, wherein the positioning geometry is arranged on the carrier film and / or on the carrier film, in particular below a printing area formed by the printing image, and wherein the positioning geometry is arranged relative to at least one position reference determined by the printing image within a predetermined position tolerance interval.

[0010] The printing plate blank typically has a rectangular format and can be designed, for example, for photochemical development. For this purpose, a printing layer is applied to the flexible carrier film. In a first step, this layer is exposed over a large area with limited depth of field from the carrier film to cure a floor layer directly adjacent to the carrier film. Subsequently, the printing image is structured using a structuring unit, which exposes the top surface of the printing plate blank facing away from the carrier film. For example, the structuring unit can be configured to locally expose those areas of the printing plate blank that will later serve as the printing image, while other areas of the printing plate blank remain unexposed.Alternatively, the structuring device is designed to selectively remove an opaque top layer from the printing plate blank. The entire printing plate blank is then exposed, with the areas still covered by the top layer remaining unexposed. Subsequently, the unexposed areas of the image layer are immediately washed away, leaving only the exposed areas on the floor layer. These exposed areas then form the raised image that protrudes from the floor layer. In a subsequent step, the image, along with its surrounding border, is separated from the printing plate blank.

[0011] This separation process can be automated if the structuring device includes a cutting unit that, depending on the position of the printed image on the printing plate, enables precise positioning of the printing plate to be separated from the printing plate blank. In this case, the desired positioning geometry is formed at an edge of the printing plate by the cutting edge created by the cutting unit when the printing plate is cut from the printing plate blank. With a suitable design of the cutting unit, the cutting edge generated during the cutting process lies within a predefined positional tolerance interval relative to at least one positional reference determined by the printed image and can therefore be used directly for positioning the printing plate on the printing cylinder without the need for further intermediate steps.

[0012] If the structuring unit does not include a cutting unit, which is the case for most structuring units, the cutting process of the printing plate from the printing plate blank is performed manually by an operator who uses a knife and, if necessary, a ruler to separate the printing plate from the printing plate blank. In this case, it cannot be guaranteed that the cutting edges produced on the printing plate during the cutting process lie within a predefined positional tolerance interval relative to at least one positional reference determined by the printed image. Consequently, none of these cutting edges can be used directly for positioning the printing plate on the printing cylinder.However, the printing plate is provided with a positioning geometry that lies within a specified positional tolerance interval relative to at least one position reference determined by the printed image and that can be used for subsequent trimming of the printing plate in order to then use the generated cut edge for positioning the printing plate.

[0013] For example, it is envisaged that the positioning geometry is formed by applying and / or introducing a scanning structure during or after the structuring of the printed image onto and / or into the carrier film, whereby the scanning structure is created with the same precision as the printed image and thus has the same tolerance properties as the printed image.

[0014] This scanning structure can be, in particular, a non-contact or contact-based, especially optical or magnetic, detectable marking, which is preferably generated in the same way as the printed image or at least applied to the printing plate by a marking device directly associated with the structuring device. Examples of such a scanning structure are markings that are applied to or incorporated into the carrier film as an inkjet print mark, a laser mark, or a groove. During a subsequent trimming process for the printing plate, this scanning structure can be used to position the cutting edge in such a way as to ensure compliance with a positional tolerance interval of less than 0.07 mm, preferably less than 0.05 mm, and particularly less than 0.03 mm, between the outer edge of the printing plate, which serves as the positioning geometry, and the printed image.

[0015] Preferably, several printing plates are cut out of the printing plate blank.

[0016] Accordingly, the method provides that the positioning geometry is formed by edge trimming of the printing plate, which is carried out during or after structuring the printed image, wherein a cut edge of the printing plate formed during the trimming process is arranged within a position tolerance interval of less than 0.07mm, preferably less than 0.05mm, in particular less than 0.03mm.

[0017] It is advantageous in the execution of the process if the edge trimming of the printing plate is carried out independently of the structuring of the printed image and if, for the execution of a trimming process, the positioning geometry formed on the carrier film and / or on the carrier film, in particular below a printing area formed by the printed image, is scanned, in particular cut off.

[0018] The object of the invention is achieved according to a second aspect of the invention by means of a printing plate for use in a flexographic printing process. The printing plate comprises a flexible carrier film made of an elastic plastic material, which has a smooth underside and a smooth top side, wherein at least one printed image is applied to the top side, which is raised from the top side, wherein a surface of the printed image defines a printing area, wherein the printed image forms at least one positional reference, and wherein a positioning geometry is formed on at least one edge region of the printing plate on the carrier film and / or on the carrier film, in particular below the printing area, which is arranged relative to the at least one positional reference within a predetermined positional tolerance interval.Typically, the printed image includes one or more geometries, particularly those located near the edge of the printing plate, such as corners or small radii. These geometries can conveniently serve as a positional reference for determining the location of the positioning geometry and thus for verifying compliance with the specified positional tolerance interval. These geometries can be, in particular, machine-readable marks (2D barcodes, e.g., Data Matrix codes, QR codes).

[0019] In a further development of the printing plate, it is provided that the positional tolerance interval is less than 0.07mm, preferably less than 0.05mm, and in particular less than 0.03mm.

[0020] In a further embodiment of the printing plate, the positioning geometry is designed as a straight outer edge of the printing plate, or as a straight line in or on the flexible carrier film, or as a rectilinear arrangement of outer edge segments of the printing plate, or as a rectilinear arrangement of markings in or on the carrier film. This allows for either contactless optical scanning of the positioning geometry or, if necessary, mechanical scanning. Optionally, the positioning geometry can be formed by a multitude of projections arranged at the edge of the printing plate or a multitude of markings on or in the carrier film, all arranged along a common straight line.

[0021] According to a further aspect of the invention, the object of the invention is achieved by a device according to claim 3. For this purpose, the device comprises a cutting device from the group consisting of: knife cutters, rotary cutters, laser cutters, water jet cutters, and hot wire cutters, as well as a scanning device configured for detecting a printed image and / or a positioning geometry at at least one edge region of a printed image applied to a printing plate, wherein the positioning geometry is arranged on the carrier film and / or on the carrier film, and a receiving device, in particular a support table, for receiving, scanning, and trimming the printing plate, wherein an actuator is arranged between the cutting device and the receiving device, which is configured to provide relative movement between the cutting device and the receiving device and which is connected to the scanning device.to form a cutting edge of the printing plate created during the trimming process, which is arranged within a positional tolerance interval of less than 0.07 mm, preferably less than 0.05 mm, and in particular less than 0.03 mm.

[0022] Advantageous embodiments of the invention are shown in the drawing. Here, the drawing shows: Figure 1: A purely schematic top view of a printing plate blank after structuring the printing layer, with the printing plates formed by the structuring process only schematically indicated; Figure 2: A schematic top view of a printing plate that was manually separated from the printing plate blank; Figure 3: A front view of a first variant of the printing plate according to the Figure 2 Figure 4 shows a front view of a second variant of the printing plate according to the Figure 2 Figure 5 shows a front view of a third variant of the printing plate according to the Figure 2Figure 6 is a purely schematic representation of a device for trimming the edges of a printing plate; Figure 7 is a schematic top view of a printing plate, in particular with the device according to the Figure 6 , edge-trimmed printing plate, Figure 8 a schematic top view of a device for applying a printing plate to a printing cylinder, and Figure 9 a side sectional view of the device according to the Figure 8 .

[0023] A purely schematic representation Figure 1The illustrated printing plate blank 1 has a rectangular shape and comprises a carrier film (not shown) made of a flexible material, as well as a printing image layer applied to the flexible carrier film. For example, the printing image layer may be formed from a photosensitive polymer and initially protected from light by a barrier layer (not shown) on the upper side of the printing plate blank 1. In a first step, the printing plate blank 1 is fully exposed to light from the underside through the carrier film to a defined penetration depth in order to cure a carrier layer directly adjacent to the carrier film, which is also referred to as the floor layer 12.Subsequently, the printing plate blank 1 can be structured in a structuring device (not shown in detail), whereby the barrier layer is selectively removed. This exposes the image layer in certain areas, allowing it to be cured in the exposed areas during a subsequent exposure process. This prevents the image layer from being washed off the floor layer in these cured areas during a subsequent washing process. After the washing process, the resulting image stands out in relief from the floor layer 12, as shown in the illustrations. Figures 3 to 5 is shown schematically.

[0024] After the washing process, individual printing plates 2 are separated from the printing plate blank 1. For example, this separation is carried out manually by an operator, possibly using a ruler. As a result, the separated printing plate 2 has a circumferential edge 3 whose position and contour are too imprecise in relation to the printed image 4 to allow the edge 3 to be used to precisely mount the printing plate 2 onto a printing cylinder in a subsequent step.

[0025] In order to provide a convenient reference for applying printing plate 2 to the printing cylinder, printing plate 2 must be designed according to the Figure 2The provision is to form a positioning geometry 5 at a distance from the printed image 4, which in a subsequent processing step is used to enable edge trimming of the printing plate 2, so that it has a cutting edge 6 that is precisely aligned with the printed image 4, at least in sections, as shown in the Figure 2 as indicated by the dashed geometry.

[0026] For the positioning geometry 5 on the printing plate 2, as shown in the Figure 2 As shown, several alternatives are available, some of which are in the Figures 3 to 5 are shown and, despite the different design of the respective positioning geometry 5, always refer to the printed image 4 and the geometries contained therein, not shown in detail and usable as a position reference, according to the representation of the Figure 2 are related.

[0027] In positioning geometry 5 according to the Figure 3This is a raised area 8 aligned parallel to an outer edge 7 of the printed image 4, which is created during the structuring process for the printed image 4 and has the same properties as the printed image 4. This ensures that the raised area 8 has the same positioning accuracy as the other parts of the printed image 4. Such a raised area 8 is also referred to as a roller bar. In a variant of the raised area 8, which is not shown in detail, it is located below a level 9 defined by a top surface 10 of the printed image 4, so that even if the printing plate 2 is used for a (test) print run before the edge trimming is carried out, the raised area 8 is not printed.

[0028] In positioning geometry 5 according to the Figure 4This is a marking 15 applied to the surface 11 of the floor layer 12, which is located in the Figure 4 for reasons of visibility, it is shown in an exaggerated form and is not part of the printed image layer 14. For example, the marking 15 can be applied to the surface 11 of the floor layer 12 during or after the structuring process, for example, using an inkjet printhead associated with the structuring device or using a laser associated with the structuring device.

[0029] In positioning geometry 5 according to the Figure 5 This is a marking 16 introduced into the floor layer 12, such as can be created, for example, by using a suitably focused laser source during or after the structuring process.

[0030] In any case, the positioning geometry 5, regardless of its individual design, can either be used for direct positioning of the printing plate 2 onto a printing cylinder by performing a contact or non-contact scanning of the positioning geometry during an assembly process for the printing plate 2.

[0031] In a preferred alternative procedure, it is provided that, prior to mounting the printing plate 2 onto the printing cylinder, the edge trimming of the printing plate 2 mentioned above takes place in order to form the cutting edge 6, so that the printing plate 2 has a permanent and easily reproducible probeable geometry, which also does not negatively affect the size of the printing plate 2.

[0032] As an example, it is planned to use printing plate 2 with a [unclear] in the Figure 6The trimming device 20, shown only schematically, is used to trim the edges in order to remove the material shown in the Figure 2 The indicated cutting edge 6 is created by referencing the positioning geometry 5. For this purpose, the trimming device 20 includes, by way of example, a support table 21 designed for a flat support of the pressure plate 2. By way of example, the support table 21 may be equipped with a vacuum device (not shown in detail) by means of which the pressure plate 2 can be reliably fixed to the support table 21 during the trimming process.

[0033] Furthermore, the trimming device 20 comprises a combination of a camera and a laser. The camera and the laser are arranged in a common working head 22, which is coupled to the support table 21 by means of a guide column 23. The guide column 23, with the working head 22 attached to it, is designed to be linearly movable, in particular in two mutually perpendicular spatial directions parallel to a surface 24 of the support table 21. A camera lens 25 and a laser lens 26 are arranged on the working head 22, the camera lens 25 being used for optical scanning of a surface 24 of the support table 21. Figure 6The printing plate 2, which is not shown in detail and rests on the support table 21, is provided. The print image captured by the camera arranged in the working head 22 is used to move the working head 22 relative to the support table 21, so that the edge trimming of the printing plate 2 can be carried out using the laser also housed in the working head 22.

[0034] It is specifically intended that the camera uses the positioning geometry 5 of the printing plate 2 to perform the trimming process on the printing plate 2, thereby ensuring the desired alignment of the cut edge 6 relative to the printed image 4. Accordingly, the requirements for the camera and laser components contained in the working head 22, as well as for the guide column 23 and the associated drive devices (not shown) for the guide column 23, are to be selected such that the cut edge 6 created during the trimming of the printing plate 2 is located within a positional tolerance interval of less than 0.07 mm, preferably less than 0.05 mm, and particularly less than 0.03 mm, whereby the positional tolerance for the cut edge 6 is determined starting from the printed image 4.

[0035] As a result of the pruning process, a [something] is created in the Figure 7A schematically represented printing plate 32 is provided, in which the cutting edge 6 lies within the aforementioned positional tolerance interval relative to the printed image 4 and thus forms a positioning geometry for the mounting process of the printing plate 32.

[0036] Further processing of this printing plate 32 is carried out using the method described in the Figures 8 and 9The schematically depicted device 40 is for applying the printing plate 32 to a printing cylinder 41. For this purpose, the device 40 comprises a machine frame 42 (shown only schematically) on which a printing cylinder receptacle 43 is rotatably mounted about a printing cylinder axis 44. The printing cylinder receptacle 43 is designed for end coupling of the printing cylinder 41 and includes, by way of example, a drive unit 45 designed as a geared motor. Furthermore, a positioning device 46 is associated with the machine frame 42, which is designed for the precise positioning of the printing plate 32 relative to the printing cylinder receptacle 43 and the printing cylinder 41 housed therein. By way of example, the positioning device 46 comprises two detection devices 47, each designed for detecting the cut edge 6 of the printing plate 32, which serves as the positioning geometry and is to be aligned transversely to the printing cylinder axis 44.Furthermore, the positioning device 46 comprises, by way of example, an adjusting means 51 formed from two guide rollers 48, 49 aligned parallel to each other, between which the printing plate 32 can be accommodated for the introduction of lateral forces aligned parallel to the printing cylinder axis 44, and a linear adjuster 50, which is used for a lateral position adjustment of the printing plate relative to the printing cylinder 41.

[0037] Additionally, it can be provided that the printing plate 32 can be pre-positioned before being provided to the device 40 by means of a stop bar (not shown in detail) aligned transversely to the printing cylinder axis 44, and with this alignment is first inserted into a working gap 52 between the two guide rollers 48, 49 and can then be placed on the printing cylinder 41 which is provided with a self-adhesive coating (not shown in detail).

[0038] During the subsequent rotation of the printing cylinder 41 around the printing cylinder axis 44, a tensile force is exerted on the printing plate 32 due to the self-adhesive coating of the printing cylinder 41, which allows the printing plate to be wound onto the printing cylinder 41 against a braking force applied by the guide rollers 48, 49. During this winding process, the two detection devices 47 each detect the cut edge 6 of the printing plate 32, which is oriented transversely to the printing cylinder axis 44, and each provide a deviation signal to a control unit 53.The control unit 53 is electrically connected to both the drive unit 45 and the linear actuator 50, thereby enabling a coordinated linear displacement of the two guide rollers 48, 49 parallel to the printing cylinder axis 44, which allows a change in the orientation of the area of ​​the printing plate 32 that comes into direct contact with the printing cylinder 41 and thus enables a correctly oriented application of the printing plate 32 to the printing cylinder 41.

Claims

1. Method for applying a printing plate (2, 32) to a printing cylinder (41), comprising the steps of: providing a printing cylinder to a printing cylinder mount (43) which is mounted on a machine frame (42) so as to be rotatable about a printing cylinder axis (44), applying a front edge of the printing plate (2, 32) to the printing cylinder (41), and initiating a rotary movement on the printing cylinder (43) in order to apply the printing plate (2, 32) to an outer surface of the printing cylinder (41) during a rotational movement of the printing cylinder (41) about the printing cylinder axis (44), wherein an alignment of the printing plate (2, 32) during the application process is performed by a positioning device (46) which is designed to provide the printing plate (2, 32) in a precisely positioned manner relative to the printing cylinder mount (43) and which has a detection device (47) for detecting a positioning geometry to be aligned transversely to the printing cylinder axis (44) (5; 6; 8; 15; 16) of the printing plate (2, 32) to be aligned transversely to the printing cylinder axis (44), and adjustment means (51) for lateral position adjustment of a printing plate section, characterized in that the detection device (47) detects a cutting edge (6) of the printing plate (2, 32) aligned transversely to the printing cylinder axis (44).

2. Method according to claim 1, characterized in that the cutting edge (6) of the printing plate (2, 32) is trimmed before the printing plate (2, 32) is applied to the printing cylinder (41) in accordance with a positioning geometry (5; 6; 8; 15; 16) on the printing plate (2, 32) with such precision that the cuting edge (6) is within a tolerance interval of less than 50 micrometers, in particular less than 30 micrometers, relative to the print image.

3. Device for applying a printing plate (2, 32) to a printing cylinder (41), with a machine frame (42) on which a printing cylinder mount (43) is mounted so that it can rotate around a printing cylinder axis (44), and with a positioning device (46) which is designed for the precise positioning of a printing plate (2, 32) relative to the printing cylinder mount (43), wherein the positioning device (46) comprises at least one detection device (47) for detecting a positioning geometry (5; 6; 8; 15; 16) of a printing plate (2, 32) to be aligned transversely to the printing cylinder axis (44), and adjustment means (51) for lateral position adjustment of a printing plate section, characterized in that the detection device (47) is designed for contact scanning of the cutting edge (6) of the printing plate (2, 32).

4. Method for producing a printing plate (2, 32), comprising the steps of: supplying a printing plate blank (1), which comprises a flexible carrier film (12) and a printing image layer (14) applied to the carrier film (12), to a structuring device; structuring a print image (4) in the print image layer (14) with the structuring device; creating a positioning geometry (5; 6; 8; 15; 16) at at least one edge area of the print image (4), wherein the positioning geometry (5; 6; 8; 15; 16) is arranged at the carrier film (12) and / or on the carrier film (12), in particular below a printing surface (10) formed by the print image (4), and wherein the positioning geometry (5; 6; 8; 15; 16) is arranged within a predetermined position tolerance interval relative to at least one position reference determined by the print image (4), wherein the positioning geometry (5; 6; 8; 15; 16) is formed by applying and / or introducing a scanning structure during the structuring of the print image (4) or after the structuring of the print image (4) onto and / or into the carrier film (12), wherein the scanning structure is arranged within a position tolerance interval of less than 0.1 mm, preferably less than 0.07 mm, in particular less than 0.05 mm, wherein the edge trimming of the printing plate (2, 32) is carried out independently of the structuring of the print image (4) and wherein the positioning geometry (5; 6; 8; 15; 16) located on the carrier film (12) and / or the positioning geometry (5; 6; 8; 15; 16) located on the carrier film (12) is scanned and cut off.