EP1916100B1 - Printing plate generation for anilox printing presses - Google Patents

Description

The present invention relates to a method and a device for producing at least one printing form for a printing method on a printing machine, wherein a first printing form is produced on the basis of first image data and with this printing form a printed image is printed on a printing material.

With the presented method and the device presented in particular problems to be solved, which in the use of colorless printing machines such. B. anilox printing machines occur.

A corresponding printing press is in the EP 0 870 609 A2 described.

In conventional offset printing machines, which have ink zones, the supply of ink is set in zones by means of a color zone control. In this way, within the printing machine, the color density and in particular the tonal value of the printed image in the corresponding zones during printing can be regulated. The control of the zone screws which regulate the amount of ink is regulated in general according to the current state of the art as a function of the printing originals for the different printing inks. The printing inks cyan, magenta, yellow and black (CMYK) are generally used in four-color printing. The printed originals separated by printing inks are also called color separations. The artwork will usually be screened and exposed with an imagesetter on the printing plates. In the past, the film exposure was planned as an intermediate step.

Today, the page description languages PostScript (PS) and PDF (portable document format) are widely used as data formats for describing the print templates. To generate the image data, the separated print templates are rasterized in a raster image processor (RIP) and converted into a corresponding matrix or bitmap. The individual pixels corresponding to the imagesetter resolution are each assigned a value as a function of the gray value to be achieved. This assignment is generally based on a threshold range. For example, For example, a grid cell may be assigned a number of pixels. Depending on the gray value of the corresponding printing original, a number of pixels assigned to this gray value is then exposed and in this way a halftone dot corresponding to the gray value is imaged. The image data takes values 0 or 1, depending on whether the pixels are imaged or not.

A plurality of exposed pixels or raster dots on a printing plate represent a corresponding pixel and depending on the number of exposed dots, a gray value corresponding to the gray value of the original pixel of the original is displayed.

Depending on the tonal value to be displayed, the platesetter used and the printing press used, there is a change in the actual tonal value which is printed by the printing press on a substrate. Depending on the expected dot gain and the corresponding parameters of the press and the platesetter, the ink keys are automatically adjusted to match the resulting print image on the substrate Tonwert is generated, which comes as close as possible to the desired. The printer is also free to regulate the amount of ink via the ink zone control in the individual ink zones so that he can regulate the color density and the tonal values within limits within the ink zones even after the exposure of the printing plates. A corresponding method to control the area coverage of a printing plate and the amounts of ink in the printing press is in the DE 10201918 A1 disclosed.

In the ink jet printing machines described above, it is not possible to regulate the ink quantity supply by means of ink fountain keys. The printer therefore has no options, in certain areas which can also correspond to ink zones to regulate the amount of ink and thus to manipulate the printed color density or the tonal value on the substrate. A manipulation of the color densities over an area which is not identical with ink zones or even extends to serve transversely is not possible even in printing machines which have ink zones.

The document DE 10 2004 021 601 A1 discloses a method that is used to acquire spectral, densitometric or color measurements on sheet-shaped substrates during the printing process in a printing machine. The measured values are determined on printed sheets moving through the printing machine and are used by means of a computer as control parameters for controlling the printing process of the sheet-fed printing press.

The document EP 1 184 176 A2 shows a method for correcting local, machine-related dyeing nonuniformities on rotary printing presses, in which first a determination of the inking behavior of the printing units of a multicolor rotary printing press takes place by means of test forms. Dyeing nonuniformities are transferred to the prepress. On the basis of the determined data on the dyeing irregularities of the test forms, the raster tone values of the color separations of a printing form are modified in such a way that the dyeing irregularities are stored locally on the printing form or films, depending on the location of their occurrence.

In Scripture EP 1 149 703 A2 a method for the ink management and the Repro printing system is described. The method is characterized in that the color used for printing and the printing paper are set. Subsequently, the multi-valued image data forming the print image is ripped and converted into binary image data. This binary data is then used in a reproduction process in which the image containing a multi-level color chart is stored on the printing plate by means of a repromechanism. Subsequently, printing is performed with this printing plate, the specified colors and the specified paper. Thereafter, the printed printing paper is picked up by an image pickup means which extracts color scale zones from the obtained image data. The ink colors of each color scale are now measured on the basis of these extracted color scale zones. From this, profile data relating to the printing ink, the type of printing paper and the regulation values of the ink or fountain solution quantity are related and stored. On the basis of this profile data, the printing ink or dampening solution quantity is then regulated during printing.

The object of the present invention is therefore to provide a method and a device with which it is possible for a printer, the color density or the tone value in a resulting print image on a substrate even after the exposure of a first printing plate within a printing machine, in particular one to manipulate colorless printing press.

This object of the invention is achieved by a method according to claim 1 and a printing system according to claim 21. Further advantageous embodiments are described in the subclaims.

According to the invention, on the basis of at least the printed image printed on the printing substrate, area-wise correction values are to be generated in the region of the printing press. These correction values are then to be used for the correction of the printing originals on which the printing is based and / or the rastered image data, and based on at least these correction values, at least one second printing form should be produced.

Depending on that, it may be at these correction values z. B. to desired changes in the tone values or color densities in a particular area of the printed image act. Depending on which colors are concerned whose separations are to be adapted, these correction values are used to correct the print templates corresponding to these colors. Of course it can also be that not the print templates, which still have to be rasterized be corrected, but directly the already rasterized image data. These are then corrections of the individual raster cells or raster points of the raster bitmap. An application of the method during a new rastering of the print templates is also conceivable and should be included according to the invention.

In order to achieve the simplest possible operation for determining the required correction values, it is advantageously provided according to the invention for the printed print image to be displayed on a monitor and areas to be marked and / or selected for the correction values to be generated.

For this purpose, z. B. the printed image on the substrate to be scanned and then displayed on a monitor. Then in the selected areas or in the marked areas Correction values are generated which correspond there to desired new tone values or color densities.

Areas that can be marked z. B. certain objects, such. B. houses or people or places within a printed image. Such a mark can z. B. be entered via a touch screen of the monitor or generated via an automatic detection of objects within the print image.

In another advantageous embodiment, it is provided that the selectable regions are provided in the manner of zones extending in the printing direction over at least the entire printed image. These zones can advantageously correspond to the color zones known to the printer. You can then z. B. 32.5 mm wide and a change in tone or color densities in the individual ink zones can be made by a printer in the manner known to him as to adjust the ink keys, instead of then set ink fountain keys it comes to generating corresponding correction values in this marked area.

In order to provide these zones to the printer in a particularly simple manner, it is provided according to the invention that these selectable areas are provided on the monitor as structures overlapping the illustrated print image. Of course, apart from zones or color zones that are provided as selectable areas, it may also be provided that interfaces within the printed image are automatically detected and provided as correspondingly selectable areas.

To the chosen correction, d. H. In order to further refine the correction values, it is provided according to the invention that the printed image shown is subdivided into zones and the zones are made up of at least three bands running longitudinally over the entire printed image. As a result, a coarse adjustment in the zones shown can first be made and finer correction values for the individual bands can be set. In particular, the correction values can always act more easily over the entire zone and additive via the corresponding bands. These bands can either be displayed or else be deposited only for the manipulation of the tonal values or color densities.

In order to prevent jumps between the individual zones within the tone values or color densities, it is advantageously provided according to the invention that the correction values are band-wise adapted to the adjacent zones, so that an adapted course results from one zone to the adjacent zones.

Particularly advantageously, it is provided that this course is adjustable. An operator is thus provided with a means by which he can achieve a visually appealing course over the entire width of a printed sheet.

In an alternative or further embodiment, it is provided that the printed image shown is divided longitudinally into adjacent segments. In this way, a mark or a selection of certain objects within the printed image is not limited to longitudinal zones but it can be easily selected areas that are within the printed image and complete be enclosed by an interface. With a corresponding marking or selection of such a region, then all segments are selected which lie within this range. For segments that are only partially within this range, it may then be provided that corresponding correction values are adapted to their proportion of that lying in the border region.

By means of a corresponding marking all segments are thus selected and the correction values are generated for these selected segments. Advantageously, it is also provided here that the correction values of the segments of the selected region are adapted to the limits of the region to the segments adjoining from the outside. Also, this adjustment should be advantageously adjustable. In particular, it is also additionally or alternatively provided that the width of the boundary region in which a corresponding adjustment is also to be adjustable. In this way, a particularly smooth course from a selected object or area to the areas outside of the selected object can take place.

According to the invention, it is provided that these correction values or correction data can be generated in the area of the printing press by a user. In order to generate adapted or corrected printing forms, it is then provided that, according to the invention, this correction data is transferred to a raster image processor (RIP) or a printing form production device. By means of the transferring correction values, the print templates or the rastered image data can then be adapted according to the specifications of the user.

So that a user can recognize the effect of the corrections made by him on the printed image, it is advantageously provided according to the invention that the RIP or the printing plate generating device, the rastered image data or the objects underlying the image data are corrected according to the correction values and then optionally after a rastering the corrected image data passes back to the printing machine and that on the basis of this corrected image data, an image of a corrected printed image is displayed. This can be z. B. be done so that only the data for the marked area are corrected and transferred back and then these corrected image data are placed on the imaged print image. In particular, it may be provided here that different transparencies of the overlapping printed image can be set. It can also lead to a complete replacement of the printed image shown at least in regions by the corrected image data. A user then has the option of very quickly by the communication of the printing press with the printing form stage d. H. with the rip or directly with a platesetter to see the results of its correction. In particular, it can of course also be provided according to the invention that, in the area of the printing press, a further rip, which may be embodied in terms of hardware or software, is provided at least for the representation of the corrected data of the printed image.

When using conventional ink zones within a printing press, it is possible for the printer to reduce or increase the intended amount of ink within predetermined limits. In order to enable a corresponding feeling for raising or reducing the amount of ink for the presented ink-less printing units, it is provided according to the invention that is printed in a further embodiment with an over-coloration and a change in the color of the Substrate is always adjusted via a correction of the screening in the printing plate production of the at least subsequent second printing form. In the production of the first printing form this over-coloration can be taken into account, thus, by correcting the screening during the production of the second printing form, it is also possible to realize an increase in the amount of ink over the screening.

Overall, the changes made to the printed image on the press can be correction values that are either absolute values of individual pixels or halftone dots, or correction values can be generated that represent the relative changes of particular pixels or halftone dots. These values can then be transferred from the printing press back to the pre-press and used there to generate another printing form.

In a particularly advantageous embodiment, it is provided that the printing process is an anilox printing process. In this ink-zone-free printing process, the presented process for the production of printing plates can be used particularly favorably. In a further particularly advantageous embodiment, it is provided that the printing form is a printing plate and that a printing platesetter separate from the printing machine is used as the printing plate production device. It does not matter where the printing platesetter is located. The print image can then be processed directly on the printing press, the generated correction values are sent back to the precursor, ie they are transferred to the printing plate setter and a special need to provide this printing plate setter in the vicinity of the printing press is not required. Thus, a great deal of flexibility is achieved.

To properties of the press itself can lead to deviating tonal values or color densities on the substrate to take into account in the printing form production, it is advantageously provided that initially a printing form is generated on the particular test forms are provided. These test forms should advantageously have control wedges, which are each assigned to one area. In such an area of the printing form z. B. may be a zonal area described above. About these control wedges irregularities in the color and / or dot gain locally locally determined in the printing of a substrate, it can then correction values based on these detected irregularities are created and these correction values can be from the press to the RIP or the printing plate forming device d. H. be transferred to the platesetter and then considered at least in the production of the first printing form. This consideration can be carried out in such a way that a corresponding local correction of the image data or of the halftone dots is already applied during the generation of the first printing form.

Furthermore, the object of the invention is achieved by a printing system comprising at least one printing press and a printing plate generating device for generating at least one printing plate for a printing method on a printing machine, wherein a first printing form is generated on the basis of first image data and with this printing form on a print image A printing material is printed to carry out the method as described above.

This printing system is characterized in that it is in the printing press to a colorless printing machine z. B. is an anilox in particular an anilox printing machine, the other is a screen provided on this screen, the printed image to be displayed, there are further provided in this printing system marking organs which are suitable for marking selected areas of the printed image shown and it should continue to be provided switching elements for setting correction values within the so marked areas. Furthermore, the printing form production device should be a printing platesetter, the printing platesetter and / or the printing machine having a raster image processor (RIP). Return lines are to be provided for transferring correction values from the printing press to the plateetter and / or RIP and back to the printing press. Furthermore, at least one confirmation element in the area of the printing press is to be provided for confirming a displayed corrected print image and / or for starting the production of a printing form on the basis of the corrected print image.

In this way, carrying out the method described above is possible with the printing system presented here.

Embodiments from which further inventive features may result but to which the invention is not limited are shown in the figures.

Fig. 1

ein Drucksystem umfassend eine Druckmaschine und einen Druckplattenbelichter,

Fig. 2

einen Ablaufplan zur Erzeugung einer korrigierten Druckplatte,

Fig. 3

eine bereichsmäßige Markierung,

Fig. 4

eine zonenweise Auswahl und

Fig. 5

die Darstellung einer Zone.

Show it:

Fig. 1

a printing system comprising a printing machine and a printing platesetter,

Fig. 2

a flow chart for generating a corrected printing plate,

Fig. 3

an area marking,

Fig. 4

a zonal selection and

Fig. 5

the representation of a zone.

Fig. 1 shows an inventive printing system with an anilox printing machine 1, which has four printing units 2 in the illustrated case. The printing units 2 have no ink fountain keys and have only a short inking unit at which an inked roller, the ink is transferred to a printing plate cylinder 5. This is an embodiment of an already known anilox inking unit. A printing plate 18 inked over the anilox roller transfers a printed image 201 onto a sheet 7 via a blanket cylinder 4. The sheet 7 is passed from an feeder stack 6 through the printing press 1 along a transport path and thus enters a printing gap 19 which is accessible from the blanket cylinder 4 and a counter-pressure cylinder 3 is formed. In this nip 19, the color is transferred to the sheet 7. The printing unit 2 should, as described, be an anilox work. In this case, both embodiments are possible in which a dampening unit is provided, or in which a waterless printing is to be performed.

The printing machine 1 shown here is therefore a sheet-fed offset printing press.

Via a communication link 8, the printing press can be controlled from a control panel 9. This control panel 9 has a monitor 12 to support the control or the control itself.

After a sheet 7 has been passed from the feeder stack 6 through the printing units 2 of the printing press 1, a complete printed image 201 has been printed on it. This print image 201 can then be detected by a corresponding detection device. In the case shown here, an external sheet-fed scanner 10 is provided, on which a proof of a sheet 7 can be placed and scanned. Alternatively, it is of course also possible to detect the sheet 7 within the printing machine 1 with a corresponding scanning device.

The sheet scanner 10 is connected via a transmission line 11 to the control panel 9. In this way, all the data of the sheet 7 can be transmitted from the sheet scanner 10 to the control panel 9 and shown here. This can be done for example on the monitor 12. Overall, it is also possible that the monitor 12 as such represents the control panel 9. It can be sufficiently large to represent a complete sheet 7 and be designed as a touch screen. In this way, all inputs to control the machine directly over the surface of the monitor 12 are feasible.

By means of controls not shown here can be operated by the control panel 9 on the one hand, the printing press 1, on the other hand, corrections to the printed image 201 can be performed. For this purpose, as in the Figures 3 and 4 shown various controls 204, 205, 206, 302, 303 be provided. These controls can either be provided in hardware on the control panel 9, or displayed on the monitor 12. The farern here is a marking member 17 is provided, with which certain areas on the printed sheet 7 shown on the monitor 12 can be marked. Via the operating elements 204, 205, 206, 302, 303, corrections can then be made in the marked areas and correction values manually set in this way. These correction values can be transmitted via a communication line 13 to a raster image processor 15 (RIP). This rip 15 is assigned to a printing platesetter 16 in the case shown here. It may further be that the rip is integrated directly in the printing platesetter 16 and / or provided as software on a computer. The Rip 15 provides the image data available with which the platesetter 16 depending on the color separation, the printing plates 18 imaged. By means of the correction values which are transmitted to the rip via the communication line 13, the print templates which are assigned to the individual color separations can be adjusted to the corrected values for the print image 201. Based on these adjusted artwork, the Rip can create 15 new image data. This image data can be transmitted back to the control panel 9 via a communication line 14 and converted to the extent that corresponding changes in a resulting print image 201 are displayed on the monitor 12. In this way, corrections made by the operating elements 204, 205, 206, 302, 303 and 17, ie changes to the printed image 201, can be displayed directly on the monitor 12. If the changes made in this way are satisfactory, ie if the printed image 201 shown corresponds to the print image desired by an operator, then an OK can be given by a corresponding operator panel and the rip 15 can transfer the corresponding rastered image data to the printing plate imagesetter 16, which is based on the thus corrected image data generated new printing plates 18 for the individual printing units 2.

In the Fig. 2 a corresponding flow chart for the production of printing plates for an anilox printing machine 1 is shown.

Within an upstream workflow, not shown here, individual pages are assembled from pictures and texts. These are imposed with appropriate software to print sheets. These imposed sheets are saved as PDF files 101. These PDF files 101 or also post script files (PS) are transferred to the Rip 15. Within the rip 15, the transferred PDF files 101 are decomposed according to the process color used in the printing machine 1 into the corresponding print templates of this color, d. H. in the appropriate color separations. These color separations are then individually screened within the rib 15 so as to produce the screened image data for the platesetter 16. These screened image data represent a bitmap of the printing plate 18 to be exposed, with each possible exposure point being represented by a screen dot. Depending on whether this grid point is to be exposed or not, a 0 or a 1 is stored within the bitmap.

The image data thus generated are transferred to the printing platesetter 16. For each printing unit 2 of the printing press 1, a printing plate 18 corresponding to the corresponding process ink is imaged within the printing plate exposer 16. Possible further process steps for the completion of the printing plate 18 are not shown here for the sake of clarity.

The printing plates 18 thus produced are inserted into the individual printing units 2 of the anilox printing machine 1. During a first printing of the anilox printing machine 1 with the first printing plates 18, first sheets 7 are printed. These sheets 7 are then scanned and evaluated in a sheet-fed scanner 10. This sheet-fed scanner 10 can be provided externally from the printing machine 1, or also integrated in it.

The picture element scanned print image 201 is displayed on the monitor 12 of a control panel 9. As already described, certain areas or objects 203 may be marked or selected here and then corrected or modified in accordance with the specifications by the user. In this way, correction values 102 are generated, which are transferred from the control panel 9 back to the Rip 15. The Rip 15 will then create new image data based on the corrected artwork. On the basis of this image data, new values for the pixels of the printed image 201 which is displayed on the control panel 9 can be determined. These corrected pixels or the corrected image data can be passed from the Rip 15 as corrected values 103 to the control panel 9. Either within the rib 15 or within the control panel 9, the pixels of a corrected printed image 201 to be displayed are then calculated on the basis of the corrected image data and finally displayed on the monitor 12 of the control panel 9. If the corrected pixels of the print image 201 thus newly represented meet the requirements of an operator, he can trigger the generation of a new corrected printing plate 18 by the printing plate imagesetter 16 via a corresponding field on the control panel 9. If the corrected print image 201 now shown does not meet his expectations, then he has the option of further correction steps to better adapt the print image to his requirements. In this case, correction values 102 are repeatedly transmitted to the rip 15, which, based on this, transmits new corrected values 103 to the control panel 9. Only after a confirmation of the corrected print image 201 by an operator, the rip 15 is caused to pass the corrected image data to the platesetter 16, which then begins with the imaging of new printing plates 18. In particular, it is possible in this case that, if only correction values for individual color separations are available, only these corrected color separations should be used to generate new ones Pressure plates 18 are used. These new printing plates 18 are re-used in the printing machine 1, where they replaced the original first printing plates 18. Sheet 7 is again printed, which is then scanned inline or offline by a sheetfed scanner 10. The new printed images 201 thus produced are displayed again on a monitor 12 of the control panel 9, and in the event that the thus corrected printed image 201 still does not meet the requirements of the user, it is possible to produce new printing plates 18 according to the described method. Otherwise, with satisfactory pressure plates 18, a complete print job can be performed in the printing press 1.

In the Fig. 3 an example of a possible regional correction of a print image 201 is shown.

Here, part of a printed sheet 7 is shown. The scanned print image 201 is shown on a monitor 12 of the control panel 9. In addition to the printed image 201 shown here, corresponding switching elements and slider regulators 204, 205 are within a correction selection area 206. The type of switching elements and slider controls within the correction selection area 206 can be selected, for example, at the control panel 9. In the case illustrated here, the correction selection area 206 is a color balance correction area. Accordingly, switching elements for brightness, highlights, midtones and shadows are shown here. A corresponding selection via the switching elements 204 can be set more precisely by means of the slider 205. The adjustment via these slider regulators 205 or switching elements 204 is applied to a marked area within the printed image 201 shown. This area can be selected directly via a marking member 17 on the monitor 12.

For this purpose, a marking 202 can be applied to the illustrated print image 201 and an object 203 can be marked. Here, in particular, further auxiliary devices are conceivable, the 203 a selection of a particular object. B. facilitate the detection of interfaces. The marking member 17 may be, for example, a stylus or a pen with which you can act directly on the monitor 12 or it may also be a trackball or a mouse, not shown here, with which you can act on the monitor 12 ,

The changes thus made in the marked area are again displayed on the monitor 12 as described. This can be done by replacing the originally displayed area or by superimposing the corrected area. For example, it is possible for certain hues, such as yellow, blue, green, magenta, to be reduced or increased. It may also be that a brightness change occurs in a certain marked area. In particular, the entire printed image can also be regarded as the marked area if this is selected. So changes over the entire pressure range are possible.

The Fig. 4 shows an example of certain selectable areas that can be selected in the area of the illustrated print image 201. These selectable areas are overlaid on the print image 201. In the case illustrated here are ink zones 301, which were placed over the entire scanned and displayed print image 201.

These color zones 301 are symbolic of the color zones of an offset printing press with zones of color zone adjustment. This allows an operator to feel with a zoned Printing machine handle as if the color zones known to him actually.

By way of color zone regulators 302, which are provided either as mechanical regulators on the control panel 9 or are virtually provided on the monitor 12, the individual ink zones 301 can be adapted to the needs of a user. Depending on the setting and use of the ink zone controller 302, corresponding correction values for all pixels that lie within the corresponding ink zone 301 are then generated and transferred to the rip 15. In the case illustrated here, the monitor display 304 additionally comprises the color zone controller 302 and a further setting and switching area 303 in addition to the illustrated printed image 201 of the sheet 7. Here, also further possible setting functions for the individual ink zones or ink zone controllers 301, 302 can be provided.

The Fig. 5 shows a representation of a color zone 301, as it is stored to generate correction values 102. The ink zone 301 is broken down into individual bands 401 and 402, these bands covering the entire sheet 7 in the longitudinal direction and occupying only a fraction of a color zone 301 transversely thereto. The ink zone 301 can be constructed of bands of different widths 401, 402. Preferably, the bands 401 in the edge regions of a color zone 301 are to be narrower than the bands 402 in the middle region of a color zone 301. The correction values 102 are then not generated by the end position via the color zone controller 302 for the entire color zone 301, but it will be for the individual Bands 401, 402 modified correction values 102 generated. Here, the correction values 102 for the bands 401 in the outer area of a color zone 301 are adapted to the color values of adjacent color zones 301. This may be, in particular, an adaptation to already corrected color values of the adjacent Color zones 301 act. The width of this adjustment range by the bands 401 can be set up in particular via other selection controller not shown here. Multiple bands 401 may then be selected for transitioning the corrections of one color zone 301 to an adjacent color zone 301.

To select an area as shown in Fig. 3 has been illustrated, the ink zones 301 may be divided into different segments 403. These segments 403 can then, depending on the setting, independent of the ink zones 301 by a marking 202, as shown in FIG Fig. 3 has been selected. Here, too, it is possible for a uniform correction to be carried out for all segments 403 of a marked object 203 via a corresponding slider 205, but the correction values 102 thus generated in the region of the marking 202 itself are modified. For this purpose, different correction values 102 result for the segments 403 which lie in the region of the marking 202 than for the segments 403 which lie within the object 203. Furthermore, it is possible to determine the number of segments 403 or their distance from the marking 202 as an adjustable parameter, so that a transition region from the correction of the marked object 203 to the rest of the migrating print image 201 can be set. In particular, it is possible via regulators, not shown here, to adjust the adjustment itself, ie their strength or slope.

In this way, changes in the resulting print image 201, which are otherwise only possible via color zones of a conventional offset printing machine, can be adjusted by communication of changes made to the control panel 9 with the rip 15 of the prepress stage for an anilox printing press 1. In particular, even changes can be made even with a conventional offset printing machine are not possible. In this case, the method would also be useful for a conventional offset printing machine. A newly created in this way printing plate 18 then meets the requirements of a user who has performed the appropriate corrections directly to the printing press 1 based on the already printed and produced sheet 7.

LIST OF REFERENCE NUMBERS

1

Aniloxdruckmaschine

2

printing unit

3

Impression cylinder

4

Blanket cylinder

5

Plate cylinder

6

feeder pile

7

bow

8th

communication link

9

control panel

10

arch scanner

11

transmission line

12

monitor

13

communication line

14

communication line

15

Raster Image Processor

16

Printing plate density

17

locating element

18

printing plate

19

nip

101

PDF File

102

correction values

103

corrected values

201

print image

202

mark

203

object

204

switching element

205

slider

206

Correction selection area

301

color zones

302

Ink zone regulator

303

Setting and changeover range

304

monitor display

401

bands

402

bands

403

segment

Claims (21)

1. Method for generating at least one printing forme for a printing process on a printing press wherein

   - a first printing forme is generated on the basis of first screened image data and

   - a print image is printed onto a printing substrate using this printing forme, characterized in that

   - based on at least this print image (201), regional correction values are generated in the region of the printing press by corrections of a user on a print image (201) displayed on a monitor,

   - these correction values are used to correct the print originals on which this print image is based and/or the first screened image data, and

   - based on at least these correction values, at least a second printing forme is generated.
2. Method according to Claim 1,
   characterized in
   that the printed print image (201) is represented on a monitor (12) and regions may be marked and/or selected for which correction values are generated.
3. Method according to Claim 1 or 2,
   characterized in
   that the correction values correspond to desired tonal values and/or colour densities.
4. Method according to Claim 2,
   characterized in
   that the selectable regions are provided as zones (301) extending at least across the entire print image in the printing direction.
5. Method according to Claim 2,
   characterized in
   that the selectable regions are provided on the monitor (12) as structures superimposed to the displayed print image (201).
6. Method according to Claim 4,
   characterized in
   that the zones (301) are composed of a minimum of three strips (401, 402) extending across the entire print image in the longitudinal direction.
7. Method according to Claims 1 and 6,
   characterized in
   that the correction values are adapted strip-wise to the adjacent zones (301), resulting in an adapted progression from one zone (301) to the adjacent zones (301).
8. Method according to Claim 7,
   characterized in
   that the progression is adjustable.
9. Method according to at least one of Claims 2, 4 and 6,
   characterized in
   that the illustrated print image (201) is subdivided into adjacent segments (403) in the longitudinal direction.
10. Method according to Claim 9,
    characterized in
    that by marking, all segments (403) of a region are selected and correction values for the selected segments (403) are generated.
11. Method according to Claim 10,
    characterized in
    that towards the borders of the region, the correction values of the segments (403) of the selected region are adapted to the segments (403) adjoining from outside.
12. Method according to Claim 11,
    characterized in
    that the adaptation and/or the border region in which an adaptation is made is adjustable.
13. Method according to Claim 1,
    characterized in
    that the correction values are transferred to a raster image processor (RIP) (15) or to a printing forme generation device.
14. Method according to Claim 13,
    characterized in
    that, the RIP (15) or the printing forme generation device corrects the screened image data or the objects on which the image data are based in accordance with the correction values and transfers corrected image data to the printing press and that an image of a corrected print image is represented based on the corrected image data.
15. Method according to any one of the preceding claims,
    characterized in
    that printing involves an overcoloration and a coloration change on the printing material is adjusted via a correction of the screen when the at least second printing forme is generated.
16. Method according to one of Claims 1 to 15,
    characterized in
    that the correction values are absolute values of individual image dots or of individual screen dots.
17. Method according to one of Claims 1 to 15,
    characterized in
    that the correction values are relative values of individual image dots or of individual screen dots representing an indication of the required correction of these dots.
18. Method according to one of the preceding claims,
    characterized in
    that the printing process is an anilox printing process.
19. Method according to any one of the preceding claims,
    characterized in
    that the printing forme is a printing plate (18) and the printing forme generation device is a plate exposure device (16) that is separate from the printing press.
20. Method according to any one of the preceding claims,
    characterized in
    that initially, test forms are generated on a printing forme, that the test forms include control wedges respectively associated with a region,
    that irregularities in the regional coloration and/or dot gains are determined,
    that correction values are calculated on the basis of the determined irregularities, that this correction values are forwarded to the RIP (15) or to the printing forme generation device, and
    that these correction values are taken into account at least for the generation of the first printing forme to correct the image data and the screen dots, respectively.
21. Printing system for carrying out the method according to any one of the preceding claims, wherein the printing system at least comprises a printing press and a printing forme generation device for generating at least one printing forme for a printing process on a printing press and wherein

    - a first printing forme is created on the basis of first image data and

    - a print image is printed on a printing material using this printing forme,

    characterized in
    that the printing press is a printing press without ink zones,
    comprises a screen for displaying the printed print image,
    marking elements for marking selected regions of the displayed print image, and actuating elements for adjusting correction values in the marked regions,
    that the printing forme generation device is a printing plate exposure device (16), that the printing plate exposure device (16) and/or the printing press have a raster image processor (15) (RIP),
    that feedback lines for transmitting the correction values from the printing press to the printing plate exposure device (16) and/or the RIP (15) are provided, and
    that at least one confirmation element is provided in the region of the printing press for confirming the displayed corrected print image and/or for starting the generation of a printing forme on the basis of this corrected print image.

Images