WO2020160886A1

WO2020160886A1 - Method for setting a colour profile in a sheet-fed offset printing press using preprinted waste sheets

Info

Publication number: WO2020160886A1
Application number: PCT/EP2020/051012
Authority: WO
Inventors: Stefan Budach; Felix Hartmann; Michael Köllmann; Harald Willeke
Original assignee: Koenig & Bauer Ag
Priority date: 2019-02-05
Filing date: 2020-01-16
Publication date: 2020-08-13
Also published as: DE102019102762A1; EP3921164A1; EP3921164B1; ES2940706T3

Abstract

The invention relates to a method for setting a colour profile in a sheet-fed offset printing press (01), in which method: the preprinted waste sheets and unprinted good sheets are used in the event of a changeover following a job change or in the event of a proof print from the relevant sheet-fed offset printing press (01); repeatedly, after each of several sets of waste sheets, at least one good sheet is passed through the sheet-fed offset printing press (01) and the waste sheets and good sheet(s) are each inked by means of at least one inking unit (04) having a plurality of ink zones each; the inked good sheets are detected as such in the sheet-fed offset printing press (01) as a result of a manual input on a control device (19) entered by an operator of the sheet-fed offset printing press (01) or automatically; and the colour profile is set by means of an ink regulator (24), wherein the colour profile is set by means of the ink regulator (24) after detection and evaluation of the inking of exclusively the good sheets. A metal sheet is preferably used as the waste sheet and/or as the good sheet.

Description

PROCEDURE FOR SETTING A COLOR PROFILE IN A

OFFSET SHEET PRINTING MACHINE USING PRE-PRINTED MAKULATURE SHEET

description

The invention relates to methods for setting a color profile in one

Sheet-fed offset printing machine according to Claim 1 or 6.

A method for setting an area coverage is known from WO 2010/091947 A1, the area coverage being provided by one on a printing substrate

The amount of printing ink transferred to the inking unit of a printing machine takes place, with an ink supply to the inking unit being switched off at least in zones or interrupted in the inking unit when a final phase of a printing process previously carried out by the printing machine is reached, with the amount remaining on the substrate side after switching off or interrupting the ink supply in the inking unit The printing ink is still transferred to the printing material in the final phase of the printing process previously carried out by the printing machine until the area coverage that takes place with the amount of printing ink transferred to the printing material corresponds to a target value for the area coverage, with a changeover of the printing machine from the one in this printing machine running printing process is carried out on a subsequent printing process in an automated control process, from which

Inking unit in the subsequent printing process the same printing ink is transferred to the printing material as in the previous printing process, the target value being the

Area coverage for a proof of the subsequent printing process

intended area coverage, the control process below

Taking into account the specified target value for the area coverage to be set is carried out.

DE 37 07 695 A1 discloses a method for the defined generation of a dem

Production-related color distribution in the inking unit of rotary printing presses Start of printing known, in which initially the values stored in a computer for the zone-wise setting of the previous print job

The metering elements and the length of the color strip are compared with the values entered in a second memory of the computer for the zone-wise setting of the color metering elements and the length of the color strip of the following print job and the zonal difference color quantities are formed from the values per color zone, which are supplemented by the zonal memory quantities of the inking unit are transported back from the rotating inking unit into the ink fountain or conveyed into the inking unit, depending on whether the difference in ink amount is positive or negative, with the number of inking unit revolutions required for this beforehand to compensate for the zonal

Differential amounts of ink is determined and only afterwards the setting of the ink metering elements and the length of the color strip to be transferred into the inking unit, which is required for the subsequent print job in the inking unit, is carried out, with this setting neither conveying color from the inking unit nor into the inking unit.

DE 10 2010 003 913 A1 describes a method for operating

Sheet-fed printing machines known, with a sheet-fed printing machine in one

Printing pass a sheet stack is laid out, which at least one

Contains waste sheets and wherein the sheets of this sheet stack are printed in a subsequent printing pass, the waste sheet in the following

Printing pass by means of a memory or sensor device

Sheet-fed printing machine is detected, this memory or sensor device interacting with a machine control, which the sheet-fed printing machine during the following printing pass depending on the memory or

Sensor device determined detection result controls.

DE 10 2013 217 099 A1 describes a method for recognizing a

Job change in a stack of sheets to be processed known, in which a sheet is marked by this in a previous printing pass at least partially remains unprinted.

The invention is based on the object of creating a method for setting a color profile in a sheet-fed offset printing machine.

The object is achieved according to the invention by the features of claim 1 or 6. The respective dependent claims relate to advantageous configurations and / or developments of the solution found.

The advantages that can be achieved with the invention are, in particular, that the printing machine can be changed over from a first printing process currently running in the printing machine to a subsequent, second printing process, quickly and economically. In addition to a saving in material costs, especially for the printing material, machine and operating costs can also be reduced because the printing machine with the subsequent second printing process is already in the good production for salable printed products after a very short time.

An embodiment of the invention is shown in the drawings and is described in more detail below.

Show it:

1 schematically shows a sheet-fed offset printing machine;

2 a first and a second each from the sheet-fed offset printing press

print job to be executed;

3 shows the time sequence of a method for setting a color profile in the sheet-fed offset printing press to be set for a new print job. When converting a sheet-fed offset printing machine from a first currently running printing process to a subsequent, second printing process, it is necessary to cancel the distribution of a printing ink to be transferred to a sheet-like printing material to be printed in this printing machine during the execution of the first printing process along a transport path in order to second printing process to be able to produce a high-quality printed product which is free from undesired feedback from the printed product produced in the first printing process.

During the execution of the first printing process along the

The distribution of this printing ink, which adjusts the transport path of the printing ink, is transverse to a transport direction of the printing material transported through the printing machine and to be printed in the process. d. R. unevenly, d. H. it is formed along a cutting line of the running transversely to the transport direction of the printing material

Transport path of the printing ink several mostly differently pronounced

Accumulations for the printing ink ultimately to be transferred to the printing material, which is due to the fact that the printing material to be printed is transported through the printing machine transversely to its transport direction due to an i. d. As a rule, a non-uniform design of a print image to be generated on the printing material absorbs printing ink unevenly.

The transport path of the printing ink leads, starting from an ink metering system belonging to an inking unit of the printing machine, through that of the relevant one

Ink metering system supplied with printing ink via a z. B. arranged on one of the printing unit cylinders belonging to a printing unit of the printing machine up to the printing material to be printed with the relevant printing ink.

Which during the execution of the first printing process along this

Adjusting the transport path transversely to the transport direction of the printing material There is an uneven distribution of the printing ink provided by the ink metering system in a rotary printing press that prints using an offset printing process

in particular on surfaces of rollers arranged in the inking unit as well as on the at least one printing form arranged on a printing unit cylinder designed as a forme cylinder and on the outer surface of another printing unit cylinder designed as a transfer cylinder cooperating with the forme cylinder.

In a printing machine, several printing units, each lined up in a row and each having their own inking unit, are provided along the transport path of the printing material in its transport direction, with at least two of these printing units being used to transfer different printing inks to the same printing material transported through the printing machine. Both sides of the

Several printing units each with their own inking unit can be provided along the transport path of the printing material. A printing machine producing a printed product in multicolor printing can run along the transport path of the printing material. B. print with the printing inks cyan, magenta, yellow and black. The inking of the respective printing unit is z. B. designed as a roller inking unit, z. B. as a lifter inking unit or as a film inking unit, these types of inking units are known to those skilled in the art. The paint dosing system, e.g. B. an ink fountain, which supplies the relevant inking unit with printing ink, has z. B. an ink ductor rotatable about its longitudinal axis and at least one metering element; Preferably, a plurality of zone-wise adjustable ink metering elements or metering elements are provided transversely to the transport direction of the printing material, in particular each controllable by means of an adjusting element. B. are designed as in a distance range of a few tenths of a millimeter to the ink ductor variable distance arranged ink knife. At least one of the inking unit belonging to the inking roller transmits the provided by the inking unit, z. B. in the arranged transversely to the transport direction of the printing material zones of the ink metering system in particular differently dosed printing ink on the at least one printing form, the z. B. is arranged on the forme cylinder assigned to this inking unit.

As mentioned, it is necessary to convert the printing press from a first to the

Printing machine currently running printing process is required for a subsequent second printing process, which cancel out the distribution of the printing ink to be transferred from an inking unit to the printing material to be printed in the printing machine during the execution of the first printing process along the transport path. In each case, on the condition that the same printing color as in the first printing process is to be transferred from the relevant inking unit of the printing machine to the printing material in the subsequent second printing process,

Implementation of this conversion, the following procedures are known from practice:

After completion of the first printing process currently running in the printing press, at least individual rollers, preferably all rollers of the relevant

Washed inking system and thus from remaining, d. H. freed of leftover ink from the first printing process. After this washing process, the relevant inking unit is adjusted to the dosage and transport of the printing ink required to carry out the subsequent second printing process. This procedure requires a lot of time and leads to a high consumption of printing ink.

A further procedure consists in stopping an ink supply from the relevant ink metering system to the inking unit or at least interrupting it in the inking unit when a final phase of the first printing process previously carried out by the printing machine is reached, with the inking unit after switching off or interrupting the ink supply The amount of printing ink remaining on the printing material side in the final phase of the printing process previously carried out by the printing machine continues, for. B. is still transferred to the printing material for a certain time, in particular until the remaining ink from the first printing process in the inking unit is at least almost used up. One such Procedure is e.g. B. from DE 10 2008 029 998 A1. With this blank printing of the inking unit, waste is generated to a not inconsiderable extent. This procedure is also time-consuming. In addition, the distribution of the printing ink, which originates from the first printing process and is perpendicular to the transport direction of the printing material, is in principle retained, which can have an unfavorable effect on the subsequent second printing process.

In a third procedure, the subsequent second is pressed

Printing process consciously with the originating from the first printing process, transversely to the transport direction of the printing material existing distribution of the printing ink, wherein during the proof of the subsequent second printing process resulting from the first printing process dosage of z. B. in the respective transverse to

The areas of the ink metering system which are arranged in the direction of transport of the printing material and which are provided for the execution of the subsequent second

The required dosage is adapted to the printing process. This procedure then leads to difficulties if, in one zone or in several zones, the area coverage of the new second printing process to be generated therein is partially or completely very low compared to the previous first printing process. In this case, the removal of the excess printing ink in the relevant zone must be carried out entirely via the printing process, i.e. H. the second printing process. This can take a long time and lead to a not inconsiderable amount of waste.

Sometimes there is also only a clean printing of the at least one printing forme arranged on a forme cylinder and the lateral surface of the transfer cylinder interacting with this forme cylinder by adding the at least one to the

Inking unit belonging to the inking roller from the relevant forme cylinder and the first printing process is continued until the first

Printing process on the at least one printing form and / or the printing ink remaining on the lateral surface of the transfer cylinder is at least almost used up. There In the inking unit, the distribution of the printing ink originating from the first printing process and transversely to the transport direction of the printing material is retained, which can have an unfavorable effect on the subsequent second printing process.

The described procedures for converting the printing machine from a first printing process currently running in the printing machine to a subsequent second printing process show that in practice the printing machine initially produces a large number of sheets of poor color when printing, until the printing machine is ready for production, in which the printing press is salable

Printed copies generated. Depending on the color profile of the pre-order and / or the method used, with which the color zones are set to their new target color, z. B. significantly more than 100

Waste sheets, sometimes even over 400 waste sheets can be generated. This high number of waste sheets is when using high-priced substrates such. B. in sheet metal printing, in which sheet metal sheets are used as the printing material, very expensive and hardly acceptable. In this context, high-priced should mean that every single unprinted sheet intended as printing material costs a few euros, so that a three-digit number of sheets that has been used up to the production-ready setting of the sheet-fed printing machine is an expensive matter and has a significant negative impact, especially with smaller print jobs beats. There is therefore a need for a method which, in particular, a

Sheet-fed offset printing machine brings it into the target coloration in each case much faster and with considerably less sheet waste when it is first printed after starting production or when printing after a job change. The aim is to save material costs when using high-priced printing materials by reducing the amount of waste as well as unproductive machine time and labor costs by shortening the printing phase. It is too

take into account that an inking unit with rollers cannot react spontaneously or abruptly with regard to the amount of printing ink transported to the printing material, it always takes a certain amount of time, based on a previous color profile, to transfer the amount of printing ink required on the printing material to a new one

to adjust the desired color profile. Every sheet-fed offset printing machine has a certain time constant for its reaction to a changed setting of ink zone openings on an inking unit, which is a certain number of times

Sheet-fed offset printing machine transported sheets, d. H. Print sheet corresponds. React to a changed setting of the ink zone openings on an inking unit

Color density values that were colored on a with this changed setting

Print sheets are recorded, typically in the form of an exponential function. In a sheet-fed offset printing machine, up to now 100 to 150 printed sheets have usually been printed until, after a changed setting of ink zone openings on an inking unit, new printed sheets colored with this changed setting appear

Set color density values in a stable manner within previously defined permissible tolerance limits. If several cycles, each with a changed setting of the ink zone openings on an inking unit, are required until the desired target inking is stable, the requirement for sheets previously produced as waste quickly adds up to several hundred printed sheets, which is extremely disadvantageous.

Fig. 1 shows an example of a detail from a sheet-fed offset printing machine 01, shown only schematically, with several, z. B. four in the transport direction T of a printed sheet 02, in particular one z. B. formed as a sheet metal sheet 02, lined up printing units 03, wherein the printed sheets 02 are guided one after the other along a transport path through this sheet-fed offset printing machine 01. Each of these printing units 03 has an inking unit 04. The respective inking unit 04 has a z. B. an ink fountain 06 and an ink ductor 07 having ink metering system as well as in a roller train transporting printing ink z. B. at least one ink transfer roller 08, possibly an ink lifter 14 and at least one, preferably several, z. B. two inking rollers 09, which are each employed on a forme cylinder 11 of the printing unit 03, or at least are adjustable, this forme cylinder 11 rolling on a transfer cylinder 12 at least during a printing process, the transfer cylinder 12 in turn being set against an impression cylinder 13, the printing sheet 02 passing through a gap formed between the transfer cylinder 12 and the impression cylinder 13. The other printing units 03 are constructed accordingly. In each of the printing units 03, a different printing ink can be transferred to the same printing sheet 02. The relevant inking unit 04, which provides the relevant printing ink, has a plurality of printing sheets 02, each lined up at right angles to the transport path

Ink zones, in each of these ink zones each one of a control unit 16 or regulating device 16 set or at least adjustable ink metering element for metering the amount of printing ink to be applied to the printing sheet 02 in the relevant ink zone. The respective paint dosing system, d. H. whose metering elements or paint metering elements and / or whose paint ductor 07 is z. B. connected via a communication network 22 at least in terms of data to the control unit 16 or regulating device 16, with at least one control command emanating from this control unit 16 or regulating device 16 by means of the metering elements or ink metering elements and / or the ink duct 07, the ink supply to the relevant inking unit 04 with regard to the amount of printing ink to be supplied to the relevant printed sheet 02 can be adjusted zone by zone.

Preferably within the sheet-fed offset printing machine 01, in particular in or on the last printing unit 03 that prints the relevant printed sheet or sheets 02, at least one is directed towards the transport path of the respective printed sheet 02

Detection device 17 arranged. During the production of this sheet-fed offset printing machine 01, the relevant detection device 17 detects at least one color density of at least one print image generated on the relevant printed sheet 02. B. densitometric and derives their respective at least one measured value as one

Color density value e.g. B. also via the communication network 22 of the

Control device 16 to. Alternatively or in addition to the detection of the color density it can be provided that the at least one detection device 17 receives a colorimetric value of at least one print image generated on the printed sheet 02, e.g. B. detected spectrophotometrically. In addition, the detection device 17 or one of the detection devices 17, for. B. be designed as an inline inspection system, the relevant detection device 17 z. B. has at least one camera, in particular an electronic, preferably video-optical camera, with which the relevant detection device 17 of the print image generated on the printed sheet 02 by a photographic image z. B. records a sequence of images. From the recorded image, ie the recorded image, the control unit 16 or regulating device 16 can, for. B. the respective color density and / or at least one colorimetric value preferably of all the printing inks involved in the structure of the print image in question z. B. be determined by separation. It can e.g. B. be provided that several printing units 03 each have at least one z. B. is assigned detection device 17 optimized for a specific printing ink. The

The detection device 17 is the printed sheet 02 in the transport direction T

The output of the respective printing unit 03 is arranged. The detection device 17 detects z. B. the color density and / or at least one colorimetric value directly in the relevant print image or in a color measuring strip formed on the relevant printed sheet 02, with several color measuring fields preferably being arranged next to one another or in a row in the relevant color measuring strip.

The measured value detected by the relevant detection device 17 forms an actual value for a z. B. on the basis of its color density detectable area coverage of at least one printing ink transferred to the relevant printed sheet 02. The concept of

Area coverage denotes a z. B. percentage specified degree of coverage of the printing material with at least one of the printing ink applied to this printing material in the printing process, the information on the area coverage on a total area of the print image or on a partial area thereof, z. B. can be related to only a single zone running through the print image in the form of a strip. The setting of the Area coverage takes place in particular with reference to several different partial areas of the same print image, preferably arranged in parallel stripes, the associated area coverage being set for several, in particular for each of these partial areas. The control unit 16 or regulating device 16 is connected in terms of data technology at least to a storage device 18 and possibly also to an operating device 19, with at least one target value for the area coverage and / or the color density and / or the at least one colorimetric value being stored in the storage device 18 , wherein the respective actual value and nominal value of the area coverage and / or the color density and / or the at least one colorimetric value relate to the same total area or partial area of the relevant print image. The operating device 19 is used for manual input of values and / or control commands to the control unit 16 or regulating device 16.

The control unit 16 or regulating device 16, the storage device 18 and the computing unit 19 can be formed in the same assembly, which is indicated in FIG. 1 by a dashed border, this assembly as a

Color regulator 24 can be designated. This assembly or at least some of its components can be used for data purposes with a control station 21 belonging to the sheet-fed offset printing machine 01, i.e. H. with a higher-level control unit, connected or designed or arranged integrated in the control station 21. With the control station 21 is z. B. a display device 23 connected for data purposes, on which at least one image captured by the relevant capture device 17 of one of the printed sheets 02 inked in the sheet-fed offset printing press 01 is displayed.

2 illustrates the changeover of the sheet-fed offset printing machine 01 from a printing process currently running in this printing machine to a subsequent one

Printing process, with the relevant print image on a print sheet 02 of a currently executed printing process (order A) in the left column of FIG. 2 and the corresponding print image on a print sheet 02 of a new one in the right column of FIG subsequent printing process (job B) is shown. Thus, FIG. 2 shows the

Initial situation and, in comparison, the desired new situation.

A method for setting a color profile in a

Sheet-fed offset printing machine 01 described, with which the sheet-fed offset printing machine 01 is transferred from a printing process currently running in this printing machine to a subsequent printing process, especially when using high-priced printing materials, e.g. B. of sheet metal, can be converted quickly and inexpensively. In this sheet-fed offset printing machine 01, several printed sheets 02 - hereinafter referred to as sheets 02 for short - are guided one after the other along a transport path through this sheet-fed offset printing machine, these sheets 02 being colored with at least one printing ink on the transport path. For inking the sheets 02, the sheet-fed offset printing press 01 has at least one inking unit 04 providing the relevant printing ink, each with a plurality of them across the transport path of the sheets 02

lined up ink zones, in each of these ink zones each having a control unit 16 set or at least adjustable ink metering element for metering the amount of printing ink to be applied to the sheet 02 in the relevant ink zone. The control unit 16 sets the color profile applicable for this inking unit 04 by setting the respective ink metering elements of the relevant inking unit 04. The setting of the respective ink metering elements of the relevant inking unit 04 is carried out with the aim of the relevant inking unit 04 printing the sheets 02 in a continuous printing of the sheet-fed offset printing machine 01 each with one

The target color is colored. To achieve this goal, the control unit 16 iteratively sets the respective color profile applicable to the respective inking unit 04 for its target color based on color density values and / or colorimetric values recorded on several of these sheets 02 and based on a recorded image of a print image applied to the respective sheet 02 a. The respective color density values and / or the respective colorimetric values and also the respective image of the relevant print image applied to the respective sheet are each given at least one connected to the control unit 16 at least in terms of data technology in the

Sheet-fed offset printing machine 01 arranged detection device 17 detected.

The setting of the respective color profile applicable to the relevant inking unit 04 for its target inking is now carried out in the following process steps:

Up to the start of the run of this sheet-fed offset printing machine 01 producing salable printed sheets 02, several packets of sheets 02 composed of different quantities of waste sheets and / or good sheets are guided along the transport path through this sheet-fed offset printing machine 01. In this case, preprinted sheets 02 each with a print image from a previous print job that deviates from the print run of the sheet-fed offset printing machine 01 are used as waste sheets, and sheets 02 that are unprinted as good sheets are used.

At least the following packs of sheets 02 are now guided one after the other through this sheet-fed offset printing machine 01, a sheet metal plate preferably being used as waste sheet and / or as good sheet: a) a first package of sheets 02 consisting of several waste sheets, b) a second package consisting of at least one good sheet, and c) at least one third package of sheets 02 each with several waste sheets and each with at least one good sheet. The waste sheets of the first package and the good sheet or sheets of the second package are each colored according to the color profile not corresponding to the target color, of which the control unit 16 when setting the color profile of the at least one inking unit 04 when converting z. B. after a job change or when printing the sheet-fed offset printing machine 01 goes out, so with a color profile, which z. B. the coloring of sheet 02 one of the current ones

The print job to be set corresponds to the previous print job.

While the said packets of sheet 02 successively through the Sheet offset printing machine 01 are performed, the control unit 16 recognizes the at least one good sheet of the second package either according to a z. B. manual input made by an operator of the sheet-fed offset printing machine 01 on the operating device 19 connected to the control unit 16 in terms of data technology or, in a higher technical expansion stage, automatically as a good sheet. With the detection of the good sheet or sheets, the control unit 16 defines a respective position of several color measurement fields, each position of these color measurement fields being arranged in one of the ink zones of the relevant inking unit 04. Following the second packet of sheets 02 passed through the sheet-fed offset printing machine 01, the control unit 16 detects the further sheets 02 passed through this sheet-fed offset printing machine 01 by means of the relevant detection device 17 to the respective one

defined positions of the color measurement fields, their respective color density values and / or colorimetric values.

In addition, the control unit 16 with the relevant detection device 17 detects at the latest at the beginning of the sheets 02 of the second package of the through the

Sheet-fed offset printing machine 01 each sheet 02 guided is an image of the print image applied to the respective sheet 02. In addition, the control unit 16 stores a master image with the recognition of the good sheet or sheets of the second package, the master image having at least one contour of the print image to be created on the sheet 02 in the production run of the sheet-fed offset printing machine 01. The control unit 16 compares the respective images captured by the respective detection device 17 of the sheets 02 fed through the sheet-fed offset printing machine 01 following the second package with the master image, the control unit 16 checking these further sheets 02 for the presence of a print image corresponding to the master image checks. The control unit 16 evaluates sheets 02 with one corresponding to the master image

Print image as a good sheet and sheet 02 with a master image not

corresponding print image as a waste sheet. The control unit 16 then allows sheets 02, which are evaluated as waste sheets, in the formation of the respective color profile is set by the control unit 16 following the second bundle of sheets 02 passed through the sheet-fed offset printing press 01,

are not taken into account, so that only sheets 02 evaluated as good sheets are used to form the respective new color profile to be set. Accordingly, starting with the sheets 02 of the third package, the control unit 16 iteratively sets the respective color profile on the relevant inking unit 04 on the basis of the respective color density values and / or colorimetric values recorded from each good sheet up to

Agreement with the respective color profile applicable to the target color.

It is preferably provided that the control unit 16 receives the respective image of at least one or more good sheets of the second package

The print image is stored and connected to the control unit 16

Display device 23 displays.

In a preferred embodiment, the control unit 16 determines the respective good sheets of the third package from several in each case at the same positions by means of color density values and / or recorded with the relevant detection device 17

colorimetric values each have a mean value and uses these mean values to set the respective color profile.

The master image can be created by the control unit 16 such that the

Control unit 16 reduces the resolution, given by its number of pixels, of the relevant originally captured image of the good sheet or sheets of the second package and uses the remaining number of pixels as an image signature representing the master image, the control unit using the image signature representing the master image to check the presence of a print image corresponding to this master image is used on sheets 02 guided along the transport path through the sheet-fed offset printing machine 01 after the master image has been created. In the event that a detection device 17 having a plurality of color channels is used to detect the respective image of the relevant print image applied to the respective sheet 02, the control unit 16 forms the respective one

Image signature of the master image z. B. separately for each color channel of the detection device 17 and uses the image signature formed by color channel of the master image to check the presence of a print image corresponding to this master image.

In principle, the master image can be formed from the respective image of the good sheet or sheets of the second package, or it is used as a master image, for example. B. a digital one

Used preview image from prepress.

In addition, it can be provided that the control unit 16 after the formation of the

Master image for sheets 02 subsequently guided through this sheet-fed offset printing machine 01 sets an axial register and / or a circumferential register and / or a color register.

When the conversion or the proof of the sheet-fed offset printing machine 01 has been carried out according to the method described above, the control unit 16 i. d. As a rule, enter the respective color profile, which is set at the end of the last third pack of sheet 02, on the relevant inking unit 04 as the color profile applicable for the production run.

In the method described here for setting at least one color profile when converting or printing the sheet-fed offset printing machine 01, typically 40 to 50 waste sheets are used for the first package. At least these waste sheets of the first package form what is known as leading waste for basic inking of the sheets 02 after the respective printing ink has run into the relevant inking unit 04. B. 10 to 15 sheets 02 are used, the control unit 16 only using the sheets recognized as good sheets in each of these third packets, the respective color profile is improved, until the coloring of the sheets 02 achieved corresponds to the respective color profile applicable to the target coloring within the previously defined permissible tolerance limits. The color profile that applies to the target coloring is accordingly set and / or adjusted step-by-step by the control unit 16 on the basis of the recognized good sheets serving as support points.

The method proposed here takes into account, on the one hand, that as a reaction to a changed setting of ink zone openings on a sheet 02 inked in the sheet-fed offset printing machine 01 with this changed setting on an inking unit 04, color density values recorded cannot change suddenly or abruptly, but that these color density values can only change after one specific time, d. H. reach a new stable state after a certain machine running time. On the other hand, the method proposed here succeeds in achieving the setting of the color profile applicable for the target inking with only the smallest possible number of high-priced sheets 02.

The proposed method for setting a color profile in a

Sheet-fed offset printing machine 01 used when converting to a

Job change or, when the sheet-fed offset printing machine 01 is pressed, preprinted waste sheets and unprinted good sheets, with at least one good sheet being repeatedly passed through the sheet-fed offset printing machine 01 after several waste sheets, i.e. in the form of several successive packages, and the waste sheets and good sheets in each case in particular by means of at least one each several color zones having inking unit 04 are colored, the colored good sheets in the sheet-fed offset printing machine 01 according to a z. B. made by an operator of the sheet-fed offset printing machine 01 manual input on an operating device 19 of the sheet-fed offset printing machine 01 concerned or automatically z. B. be recognized as such by means of image recognition, ie as a good sheet, and the setting of the color profile by means of an inking unit 04 acting color regulator 24 after a detection and evaluation of the respective

Coloring alone, d. H. only the recognized good sheet takes place. Further details of this process have been previously described, e.g. B. that the detection of the respective coloring of the waste sheets and good sheets in particular inline, d. H. in the sheet offset printing machine concerned 01 with a z. B. designed as a camera detection device 17 takes place and / or that the automatic detection of

Good sheet takes place by means of image recognition and / or that the evaluation of the respective coloring of the recognized good sheet takes place on the basis of color density values and / or colorimetric values recorded on these good sheets.

3 again illustrates the time sequence of the proposed method for setting a color profile in a sheet-fed offset printing press 01 to be set for a new print job using a time line t running from left to right. It is assumed that at a point in time t0 the conversion of the relevant

Sheet-fed offset printing machine 01 after a job change or the printing of a new print job begins.

The proposed method starts with the fact that, for. B. at a feeder

Sheet-fed offset printing machine 01 already provided with a print image from at least one previous printing process, d. H. In each case printed and in each case not intended for sale waste sheets are guided through the sheet-fed offset printing machine 01 and through the at least one inking unit 04 of this

Sheet offset printing machine 01 are colored. This is a first package P1 of sheet 02 with z. B. 40 to 50 waste sheets that are successively passed through this sheet-fed offset printing machine 01. At time t0, a color profile no longer corresponding to the previous print job, but in any case not yet corresponding to the target color of the new print job, is set on the relevant inking units 04. During the phase of the sheet-fed offset printing machine 01 which inks the first package P1 of sheets 02, there is an inflow of printing ink generally not reduced or even stopped for the respective inking unit 04.

At time t1, all of the waste sheets of the first package P1 of sheets 02 have been fed through the sheet-fed offset printing press 01. The phase of the sheet-fed offset printing press 01 which inks the first package P1 of sheet 02 is thus ended. From the point in time t1, at least one unprinted good sheet is used as a second package P2 of sheets 02 z. B. provided at the feeder of the sheet-fed offset printing machine 01 and then passed through the sheet-fed offset printing machine 01 to color it. Either as a result of a manual input made by an operator of the sheet-fed offset printing machine 01 on an operating device 19 connected to this sheet-fed offset printing machine 01 at least in terms of data, or the good sheet or sheets are recognized as such automatically. With the detection of the good sheet (s) of the second package P2, a respective position of several color measurement fields is also established with reference to the sheets 02 of the new print job to be processed, at which, in the case of further sheets 02 guided through the sheet-fed offset printing machine 01, a sheet-fed offset printing machine 01 arranged in this and with a control unit

16 of this sheet-fed offset printing machine 01 connected at least in terms of data

Detection device 17 whose respective color density values and / or colorimetric values are detected. From the time t1 at the latest, the above-mentioned or another detection device 17 is used to transfer the sheets 02 of the second package P2 and all others guided through this sheet-fed offset printing press 01 through the

Sheet 02 guided sheet offset printing machine 01 each captures an image of the print image applied to the respective sheet 02. With the detection of the good sheet or sheets of the second package P2, the

Control unit 16 stores a master image, the master image having at least one contour of the print image to be created on sheet 02 in the production run of sheet-fed offset printing machine 01 according to the new print job to be processed. From time t2, the control unit 16 compares the respective detection device with the relevant detection device

17 captured images of the subsequent to the second packet P2 by the Sheet-fed offset printing machine 01 each guided sheet 02 with the stored master image, the control unit 16 checking these further sheets 02 for the presence of a print image corresponding to the master image. In this check, the control unit 16 evaluates sheet 02 with a print image corresponding to the master image as a good sheet and sheet 02 with a print image not corresponding to the master image as a waste sheet. At time t2, the control unit 16 also begins iteratively the respective color profile on the relevant inking unit 04 based on the respective color density values and / or colorimetric values recorded from good sheets until it corresponds to the respective color profile applicable to the target color

set, from the point in time t2 several packages P3n each consisting of several waste sheets and at least one good sheet through them

Sheet-fed offset printing machine 01 are performed. In the formation of the respective color profile, which is generated by the control unit 16 following the second by the

Sheet-fed offset printing machine 01, the package P2 of sheets 02, that is to say is set from time t2, does not take into account sheets 02 that it considers to be waste sheets. Only the sheets 02 recognized by the control unit 16 as good sheets each serve as support points for the step-by-step setting of the respective color profile applicable to the target inking.

After all sheets 02 of the third packages P3n are successively passed through the

Sheet offset printing machine 01 have been performed and the respective color profile has been set based on the sheet 02 recognized as a good sheet in increasingly better correspondence with the color profile applicable for the target inking, it is assumed that the sheet-fed offset printing machine 01 will continue printing at time t3 and the control unit 16 switches on and / or the color regulator 24 in a corresponding operating mode.

List of reference symbols

01 sheet-fed printing press

02 print sheet, sheet

03 printing unit

04 inking unit

05 -

06 color box

07 Ink ductor

08 Ink transfer roller 09 Ink application roller

10

11 forme cylinder

12 transfer cylinders

13 impression cylinder

14 color lifters

15 -

16 control unit, regulating device

17 acquisition device

18 Storage facility

19 Control device

20th

21 Control center

22 Communication network

23 Display device

24 color controls P1 first package of sheet (02) P2 second package of sheet (02) P3n third package of sheet (02) t timeline

tO point in time

t1 point in time

t2 point in time

t3 point in time

T direction of transport

Claims

Expectations

1. A method for setting a color profile in a sheet-fed offset printing machine (01), in which preprinted waste sheets and unprinted good sheets are used in the event of a changeover after a job change or when printing the sheet-fed offset printing machine (01) in question, in which at least one good sheet is used repeatedly after several waste sheets through the

Sheet-fed offset printing machine (01) is performed and the waste sheets and good sheets are each colored by means of at least one inking unit (04) each having several color zones, in which the colored good sheets in the sheet-fed offset printing machine (01) according to an operator of the

Sheet offset printing machine (01) made manual input on an operating device (19) or automatically recognized as such, in which the setting of the color profile is carried out by means of a color regulator (24), the setting of the color profile by means of the color regulator (24) after detection and Evaluation of the respective coloring takes place exclusively of the recognized good sheets.

2. The method according to claim 1, characterized in that the detection of the

The respective coloring of the waste sheets and good sheets is carried out inline.

3. The method according to claim 1 or 2, characterized in that the detection of the respective coloring of the waste sheets and good sheets is carried out with a detection device (17) designed as a camera.

4. The method according to claim 1 or 2 or 3, characterized in that the

automatic recognition of the good sheets by means of image recognition takes place.

5. The method according to claim 1 or 2 or 3 or 4, characterized in that the Evaluation of the respective coloring of the recognized good sheets takes place on the basis of color density values and / or colorimetric values recorded on this good sheet.

6. A method for setting a color profile in a sheet-fed offset printing machine (01), several sheets (02) being guided one after the other along a transport path through this sheet-fed offset printing machine (01), these sheets (02) being colored with at least one printing ink on the transport path, with the sheet-fed offset printing machine (01) has at least one inking unit (04) providing the relevant printing ink, each with a plurality of ink zones lined up transversely to the transport path of the sheets (02), in each of which

Inking zones each have an ink metering element set or at least adjustable by a control unit (16) for metering the amount of printing ink to be applied to the sheet (02) in the relevant ink zone, the control unit (16) by setting the respective ink metering elements of the relevant inking unit ( 04) sets the color profile applicable to this inking unit (04), the relevant inking unit (04) inking the sheets (02) in a production run of the sheet-fed offset printing machine (01) each with a target color, the control unit (16) setting the respective for the relevant Inking unit (04) sets the applicable color profile in each case iteratively on the basis of color density values and / or colorimetric values recorded on several of these sheets (02) and on the basis of a recorded image of a print image applied to the respective sheet (02), the respective color density values and / or the respective colorimetric values and also the respective ige images of the relevant print image applied to the respective sheet (02) are recorded with at least one detection device (17), which is connected to the control unit (16) for data purposes, and directed towards the transport path of the respective sheet (02), characterized in that,

a. that up to the start of the production run of this sheet-fed offset printing machine (01), several of different quantities of waste sheets in succession and / or packs of sheets (02) composed of good sheets are guided along the transport path through this sheet-fed offset printing machine (01), with each preprinted sheet (02) as waste sheets with a sheet (02) that deviates from the continuous printing of the sheet-fed offset printing machine (01)

Print image from a previous print job and unprinted sheets (02) can be used as good sheets, with at least the following packets of sheets (02) being guided one after the other through this sheet-fed offset printing machine (01):

a.a. a first package of sheets (02) consisting of several

Waste sheet,

from. a second package consisting of at least one good sheet, a.c. at least a third package of sheets (02) each with several waste sheets and each with at least one good sheet, a.d. wherein the waste sheets of the first package and the or the

Good sheets of the second package are each colored according to the color profile that does not correspond to the target color, from which the control unit (16) starts when setting the color profile of the at least one inking unit (04),

b. that the control unit (16) automatically recognizes the at least one good sheet of the second package as a good sheet as a result of a manual input on an operating device (19) connected to the control unit (16) in terms of data technology, and with the detection of the good sheet or sheets a respective position of several color measurement fields defines, each position of these color measurement fields in one of the color zones of the

relevant inking unit (04) is arranged,

c. that the control unit (16) following the second by the

Sheet-fed offset printing machine (01) guided package of sheets (02) for further sheets (02) guided through the sheet-fed offset printing machine (01) by means of the relevant detection device (17) to the respective fixed Positions of the color measurement fields whose respective color density values and / or colorimetric values are recorded,

d. that the control unit (16) with the relevant detection device (17) at the latest at the beginning of the sheets (02) of the second package of the sheets (02) fed through the sheet-fed offset printing machine (01) in each case an image of the print image applied to the respective sheet (02) detected,

e. that the control unit (16) stores a master image with the detection of the good sheet or sheets of the second package, the master image having at least one contour of the print image to be created on the sheet (02) during production of the sheet-fed offset printing machine (01),

f. that the control unit (16) the respective with the relevant

Acquisition device (17) acquired images of the sheets (02) fed through the sheet-fed offset printing machine (01) following the second package in each case with the master image, the control unit (16) comparing these further sheets (02) for the presence of one of the master images checks corresponding print image, the control unit (16) evaluating sheet (02) with a print image corresponding to the master image as a good sheet and sheet (02) with a print image not corresponding to the master image as a waste sheet, the control unit (16) as

Waste sheets scored sheets (02) in the formation of the respective

Does not take into account the color profile that is set by the control unit (16) after the second bundle of sheets (02) passed through the sheet-fed offset printing machine (01),

G. that the control unit (16), starting with the sheets (02) of the third package, iteratively applies the respective color profile to the relevant inking unit (04) based on the respective color density values and / or colorimetric values recorded by the good sheets until they match the respective applicable color for the target color Color profile.

7. The method according to claim 6, characterized in that the control unit (16) stores the respective image of the relevant print image from at least one or more good sheets of the second package and displays it on a display device (23) connected to the control unit (16).

8. The method according to claim 6 or 7, characterized in that the control unit (16) determines a mean value from several each at the same positions of the respective good sheets of the third package by means of color density values and / or colorimetric values recorded with the respective detection device (17) and these mean values are used to set the respective color profile.

9. The method according to claim 6 or 7 or 8, characterized in that the

Master image is created by the control unit (16) in such a way that the control unit (16) reduces the resolution, given by its amount of pixels, of the relevant originally captured image of the good sheet or sheets of the second package and the remaining amount of pixels as a master image

representing image signature is used, the control unit (16) using the image signature representing the master image to check the presence of a print image corresponding to this master image on sheets (02) which are guided along the transport path through the sheet-fed offset printing machine (01) after the master image has been created.

10. The method according to claim 9, characterized in that for detecting the

respective image of the respective on the respective sheet (02)

applied print image having multiple color channels

Detection device (17) is used, the control unit (16) the respective image signature of the master image separately for each color channel of the

Forms detection device (17) and used to check the presence of a print image corresponding to this master image.

11. The method according to claim 6 or 7 or 8 or 9 or 10, characterized in that the master image is formed from the respective image of the good sheet or sheets of the second package.

12. The method according to claim 6 or 7 or 8 or 9 or 10, characterized in that a digital preview image from a prepress stage is used as the master image.

13. The method according to claim 6 or 7 or 8 or 9 or 10 or 11 or 12, characterized in that the control unit (17) after forming the master image for sheets (02) subsequently guided through this sheet-fed offset printing machine (01) an axial register and / or sets a circumferential register and / or a color register.

14. The method according to claim 6 or 7 or 8 or 9 or 10 or 11 or 12 or 13, characterized in that the control unit (16) the respective color profile, which is set at the end of the last third package of sheets (02) sets the relevant inking unit (04) as the color profile applicable for the production run.

15. The method according to claim 6 or 7 or 8 or 9 or 10 or 11 or 12 or 13 or 14, characterized in that for the first package 40 to 50

Waste sheets can be used.

16. The method according to claim 6 or 7 or 8 or 9 or 10 or 11 or 12 or 13 or 14 or 15, characterized in that 10 to 15 sheets (02) are used for each of the third packages.

17. The method according to claim 1 or 2 or 3 or 4 or 5 or 6 or 7 or 8 or 9 or 10 or 11 or 12 or 13 or 14 or 15 or 16, characterized in that that a sheet of metal is used as a waste sheet and / or as a good sheet.