DE102019102762A1 - Process for setting a color profile in a sheetfed offset press - Google Patents

Abstract

The invention relates to a method for setting a color profile in a sheet-fed offset printing machine, in which preprinted waste sheets and unprinted good sheets are used when retrofitting after a job change or when printing the sheet-fed offset printing machine in question, in which at least one good sheet is repeatedly passed through the sheet-fed offset printing machine after several waste sheets and the waste sheets and good sheets are each colored in particular by means of at least one inking unit each having several color zones, in which the good sheet in the sheet-fed offset printing machine according to a z. B. made by an operator of the sheet-fed offset printing machine manual input on an operating device or automatically z. B. can be recognized as such by means of image recognition and the setting of the color profile by means of a color regulator takes place after detection and evaluation of the respective coloring exclusively the recognized good sheets. A sheet metal sheet is or are preferably used as a waste sheet and / or as a good sheet.

Description

The invention relates to a method for setting a color profile in a sheetfed offset printing press according to claim 1 or 3.

Through the WO 2010/091947 A1 A method for setting an area coverage is known, the area coverage being carried out by a quantity of printing ink transferred to a printing material from an inking unit of a printing press, with an ink supply to the inking unit being switched off or at least in zones upon reaching a final phase of a printing process previously carried out by the printing press is interrupted in the inking unit, the amount of printing ink remaining on the printing material side after the ink supply has been switched off or interrupted in the final phase of the printing process previously carried out by the printing press is transferred to the printing material until the amount of printing ink transferred to the printing material area coverage takes place corresponds to a target value of the area coverage, with a changeover of the printing press from the printing process currently running in this printing press to a subsequent printing process in an automated control process ss is carried out, the same printing ink being transferred to the printing material from the inking unit in the subsequent printing process as in the previous printing process, the target value of the area coverage corresponding to the area coverage provided for a printing of the subsequent printing process, the control process taking into account the predetermined target value for the area coverage to be set is carried out.

Through the DE 37 07 695 A1 A method for the defined generation of a color distribution close to production in the inking unit of rotary printing presses before the start of printing is known, in which the values of the metering elements and the length of the color strip, which are stored in a computer in the previous print job, are first stored in a computer with a second memory of the computer entered values for the zone-wise setting of the ink metering elements and the length of the color strip of the following print job are compared and the values for each ink zone are used to form the zonal difference ink quantities, which are supplemented by the zonal storage quantities of the inking unit from the rotating inking unit and transported back into the inking box or into that Inking units are promoted depending on whether the difference in color quantity is positive or negative, the number of inking unit revolutions required for this until the zonal difference in color quantities being equalized, and only then the for the subsequent print job in the inking unit, the required setting of the ink metering elements and the length of the color strip to be transferred to the inking unit is carried out, with this setting ink neither being conveyed from the inking unit nor into the inking unit.

The invention has for its object to provide a method for setting a color profile in a sheetfed offset printing press.

The object is achieved by the features of claim 1 or 3. The respective dependent claims relate to advantageous refinements and / or developments of the solution found.

The advantages that can be achieved with the invention consist in particular in that the conversion of the printing press from a first printing process currently running in the printing press to a subsequent second printing process takes place quickly and economically. In addition to saving material costs, in particular for the printing substrate, machine and operating costs can also be reduced, because the printing press with the subsequent second printing process reaches the good production that produces salable printing products after a very short time.

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

• 1 schematisch eine Bogenoffsetdruckmaschine;
• 2 einen ersten und einen zweiten jeweils von der Bogenoffsetdruckmaschine auszuführenden Druckauftrag;
• 3 den zeitlichen Ablauf eines Verfahrens zur Einstellung eines Farbprofils in der auf einen neuen Druckauftrag einzustellenden Bogenoffsetdruckmaschine.

Show it:

• 1 schematically a sheetfed offset printing machine;
• 2nd a first and a second print job each to be executed by the sheet-fed offset printing press;
• 3rd the timing of a process for setting a color profile in the sheetfed offset press to be set for a new print job.

When converting a sheetfed offset printing press from a first printing process currently running to a subsequent second printing process, it is necessary to cancel a distribution of a printing ink to be transferred to a sheet-like printing material to be printed in this printing press during the execution of the first printing process in order to im to be able to produce a high-quality printed product in the second printing process, which is free from an undesirable reaction from the printed product produced in the first printing process.

Which occur during the execution of the first printing process along the transport path of the The distribution of this printing ink that adjusts the printing ink is generally uneven across a transport direction of the printing material that is transported through the printing press and is to be printed, that is to say, a number of mostly differently formed clusters for the ultimately form along a cutting line of the printing material transport path that runs transverse to the transport direction of the printing material printing ink to be transferred to the printing material, which is due to the fact that the printing material to be printed receives unevenly during its transport through the printing machine transversely to its transport direction due to a generally uneven design of a print image to be produced on the printing material.

The transport path of the printing ink leads from an ink metering system belonging to an inking unit of the printing press through the inking unit supplied with ink by the respective ink metering system via a z. B. on one of the printing unit cylinders belonging to a printing unit cylinder arranged printing form up to the printing material to be printed with the relevant printing ink. The uneven distribution of the printing ink provided by the ink metering system, which occurs during the execution of the first printing process along this transport path transversely to the transport direction of the printing material, exists in particular in the case of a rotary printing press printing in an offset printing method, in particular on surfaces of rollers arranged in the inking unit and on the at least one on a forme cylinder trained printing unit cylinder arranged printing form and on the outer surface of another with the forme cylinder interacting as a transfer cylinder designed as a transfer cylinder.

In a printing press, along the transport path of the printing material in its transport direction, usually a plurality of printing units arranged in a row, each with its own inking unit, are provided, with at least two of these printing units transferring different printing inks to the same printing material transported by the printing machine. A plurality of printing units, each with its own inking unit, can also be provided on both sides of the transport path of the printing material. A printing machine producing a printed product in multicolor printing can move this along the transport path of the printing material, e.g. B. with the printing inks cyan, magenta, yellow and black. The inking unit of the respective printing unit is z. B. formed as a roller inking unit, for. B. as a lifter inking unit or as a film inking unit, these types of inking unit are known to the person skilled in the art. The color metering system, e.g. B. an ink fountain, which supplies the inking unit in question with printing ink, z. B. a rotatable about its longitudinal axis ink ductor and at least one dosing; Preferably, a plurality of zone-adjustable ink metering elements or metering elements are provided transversely to the direction of transport of the printing material, these ink metering elements or metering elements, e.g. B. are designed in a distance range of a few tenths of a millimeter to the ink duct arranged variable color knife. At least one inking roller belonging to the inking unit transfers the inking roller provided by the inking unit, e.g. B. in the transverse to the transport direction of the substrate arranged 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.

• Nach Beendigung des ersten in der Druckmaschine aktuell laufenden Druckprozesses werden zumindest einzelne Walzen, vorzugsweise alle Walzen des betreffenden Farbwerks gewaschen und damit von restlicher, d. h. vom ersten Druckprozess übrig gebliebener Druckfarbe befreit. Nach diesem Waschvorgang wird das betreffende Farbwerk auf die Dosierung und den Transport der zur Ausführung des nachfolgenden zweiten Druckprozesses erforderlichen Druckfarbe eingestellt. Diese Vorgehensweise erfordert einen hohen Zeitaufwand und führt zu einem hohen Verbrauch an Druckfarbe.

As mentioned, in order to convert the printing press from a first printing process currently running in the printing press to a subsequent second printing process, it is necessary to adjust the distribution of the printing medium to be printed on the printing press from the inking unit during the execution of the first printing process along the transport path the ink to be transferred. The following procedures are known from practice for carrying out this changeover, provided that the relevant inking unit of the printing press is to transfer the same printing ink to the printing material in the subsequent second printing process as in the first printing process:

• After the end of the first printing process currently running in the printing press, at least individual rollers, preferably all rollers of the inking unit in question, are washed and thus freed from residual printing ink, ie, ink remaining from the first printing process. After this washing process, the inking unit in question is set to meter and transport 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 switching off or at least interrupting an ink supply to the inking unit from the relevant ink metering system, 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 has been reached, with the ink supply being switched off or interrupted in the inking unit Quantity of printing ink remaining on the substrate side in the final phase of the printing process previously carried out by the printing press, for. B. still for a certain time on the substrate is transmitted, in particular until the ink remaining in the inking unit from the first printing process is at least almost used up. Such a method is e.g. B. from the DE 10 2008 029 998 A1 known. With this blank printing of the inking unit, waste is produced to a not inconsiderable degree. This procedure is also time-consuming. In addition, the distribution of the printing ink originating from the first printing process and existing transversely to the transport direction of the printing material is in principle retained, which can adversely affect the pressure of the subsequent second printing process.

In a third procedure, the subsequent second printing process is deliberately carried out with the distribution of the printing ink originating from the first printing process and transverse to the transport direction of the printing material, while during the printing of the subsequent second printing process the metering of the z. B. in the respective transverse to the transport direction of the substrate arranged zones of the ink metering ink provided to the dosage required to carry out the subsequent second printing process. This procedure 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 very small in places or completely in comparison to the previous first printing process. In this case, the removal of the excess ink in the zone in question must be carried out completely via the printing process, i. H. the second printing process. This can take a long time and lead to a not inconsiderable amount of waste.

Variously, the at least one printing forme arranged on a forme cylinder and the outer surface of the transfer cylinder interacting with this forme cylinder are also only cleanly printed by switching off the at least one inking roller belonging to the inking unit from the relevant forme cylinder and continuing the first printing process until the first printing process on the at least one printing form and / or the printing ink remaining on the outer surface of the transfer cylinder is at least almost used up. In the inking unit, the distribution of the printing ink resulting from the first printing process and existing transversely to the transport direction of the printing material is retained, which can adversely affect the pressure of the subsequent second printing process.

The described procedures for converting the printing press from a first printing process currently running in the printing press to a subsequent second printing process show that the printing press in practice initially produces a large number of sheets of defective coloring until the printing press is ready for continued printing, in which the press produces salable print copies. Depending on the color profile of the pre-order and / or the method used, with which the color zones are adjusted to their new target color, z. B. significantly more than 100 waste sheets, sometimes even over 400 waste sheets. This high number of waste sheets is when using high-priced substrates, e.g. B. in sheet metal printing, in which sheet-like metal sheets are used as printing material, very expensive and hardly acceptable. In this context, high-priced means that each individual blank sheet intended as a printing material already costs a few euros, so that a customary consumption of a three-digit number of sheets up to the production-ready setting of the sheet printing machine is an expensive affair and has a considerable negative impact, especially for smaller print jobs beats. There is therefore a need for a method which, in particular, brings a sheet-fed offset printing press into the target inking much faster and with significantly less waste as a result of a first proof after a start of production or a proof after a job change. The aim is to save material costs when using high-priced printing materials by reducing the amount of waste and unproductive machine time and labor costs by shortening the pressure phase. It should be taken into account that an inking unit with rollers cannot react spontaneously or erratically with regard to the amount of printing ink transported to the printing material, but always takes a certain amount of time, starting from a previous color profile, to convert the amount of printing ink required on the printing material to a new desired color profile adapt. Each sheetfed offset printing press therefore has a certain time constant for its reaction to a changed setting of ink zone openings in an inking unit, which corresponds to a certain number of sheets transported by this sheetfed offset printing press, ie printed sheets. Color density values, which are recorded on a printed sheet inked with this changed setting, typically react in the form of an exponential function to a changed setting of ink zone openings on an inking unit. Up to now, 100 to 150 printing sheets have usually been printed in a sheetfed offset printing press until, after a change in the setting of ink zone openings on an inking unit, new ink density values are set stable within previously defined permissible tolerance limits on printing sheets inked with this changed setting. If several cycles with a changed setting of If ink zone openings are required on an inking unit until the desired target inking is stable, the need for sheets previously produced as waste quickly adds up to several hundred printed sheets, which is extremely disadvantageous.

The 1 shows an example of a section from a sheet-fed offset printing machine shown only schematically 01 , with several, e.g. B. four in the direction of transport T of a printed sheet 02 , in particular a z. B. formed as a sheet of printed sheet 02 , printing units arranged in a row 03 , the printed sheet 02 one after the other along a transport route through this sheetfed offset printing machine 01 be performed. Each of these printing units 03 each has an inking unit 04 on. The respective inking unit 04 has a z. B. a paint box 06 and a color doctor 07 having ink metering system and in a roller transporting printing ink z. B. at least one ink transfer roller 08 , possibly a paint lifter 14 and at least one, preferably several, e.g. B. two inking rollers 09 , each on a forme cylinder 11 of the printing unit 03 are employed or at least employable, this forme cylinder 11 at least during a printing process on a transfer cylinder 12th rolls off, the transfer cylinder 12th in turn against an impression cylinder 13 is employed, the printed sheet 02 one between the transfer cylinder 12th and the impression cylinder 13 formed gap passes through. The other printing units 03 are structured accordingly. In each of the printing units 03 can use a different ink on the same sheet 02 be transmitted. The relevant inking unit providing the printing ink in question 04 has several each across the transport path of the printed sheets 02 adjacent color zones, one in each of these color zones by a control unit 16 or control device 16 adjusted or at least adjustable ink metering element for metering the ink sheet in the relevant ink zone 02 amount of ink to be applied is arranged. The respective ink metering system, ie its metering elements or ink metering elements and / or its ink ductor 07 is z. B. over a communication network 22 at least in terms of data technology with the control unit 16 or control device 16 connected, being by at least one of this control unit 16 or control device 16 outgoing control command by means of the metering elements or ink metering elements and / or the color ductor 07 the ink supply to the inking unit in question 04 with regard to the printing sheet in question 02 amount of printing ink to be fed is adjustable zone by zone.

Preferably within the sheetfed offset press 01 , in particular in or on the last of the printing sheet or sheets concerned 02 printing unit 03 is on the transport route of the respective printed sheet 02 directed at least one detection device 17th arranged. The relevant registration device 17th captured during the production of this sheetfed offset press 01 of at least one on the relevant sheet 02 generated print image at least one color density z. B. densitometric and passes their respective at least one measured value as a color density value z. B. also over the communication network 22 the control device 16 to. As an alternative or in addition to the detection of the color density, it can be provided that the at least one detection device 17th a colorimetric value of at least one on the printed sheet 02 generated print image z. B. recorded spectrophotometrically. In addition, the detection device 17th or one of the detection devices 17th e.g. B. be designed as an inline inspection system, the relevant detection device 17th e.g. B. has at least one camera, in particular an electronic, preferably video-optical camera, with which the relevant detection device 17th of that on the press sheet 02 generated print image by a photographic illustration z. B. takes a sequence of images. From the captured image, ie the captured image, the control unit can 16 or control device 16 e.g. B. the respective color density and / or at least one colorimetric value, preferably of all of the printing inks involved in the construction of the print image in question, e.g. B. can be determined by separation. It can e.g. B. be provided that several printing units 03 at least one z. B. for a certain printing ink optimized detection device 17th assigned. The detection device 17th is in the direction of transport T the press sheet 02 at the exit of the respective printing unit 03 arranged. The detection device 17th captured e.g. B. the color density and / or at least one colorimetric value directly in the print image in question or in one on the print sheet in question 02 trained color measuring strips, wherein in the color measuring strip in question, a plurality of color measuring fields are preferably arranged side by side or in a row.

The one from the relevant detection device 17th the measured value forms an actual value for a z. B. based on their color density detectable area coverage of at least one on the relevant sheet 02 transferred ink. The concept of area coverage denotes a z. B. percentage of coverage of the printing material with at least one of the printing ink applied to this printing material in the printing process, the indication of the area coverage on an entire surface of the printed image or on a partial surface of the same, eg. B. can be related to only a single, the printed image strip-shaped zone. The area coverage is set in particular with reference to a number of different partial areas of the same printed image, preferably arranged in parallel strips, the associated area coverage being set for a number of, in particular for each of these partial areas. The control unit 16 or control device 16 is at least with a storage device 18th and possibly also with an operating device 19th each connected in terms of data technology, with in the storage device 18th In each case at least one setpoint for the area coverage and / or the color density and / or the at least one colorimetric value is stored, the respective actual value and setpoint of the area coverage and / or the color density and / or the at least one colorimetric value each being based on the same total area or Obtain partial area of the relevant print image. The control device 19th is used for manual input of values and / or control commands to the control unit 16 or control device 16 .

The control unit 16 or control device 16 , the storage device 18th and the arithmetic unit 19th can be formed in the same assembly, which in the 1 is indicated by a dashed border, this assembly being a color control 24th can be designated. In terms of data technology, this assembly or at least some of its components can be connected to the sheetfed offset printing press 01 belonging control center 21 , ie connected to a higher-level control unit, or in the control center 21 be integrated or arranged. With the control center 21 is z. B. a display device 23 technically connected, on which at least one with the relevant detection device 17th captured image from one of the sheetfed offset presses 01 inked printed sheet 02 is shown.

2nd illustrates the conversion of the sheetfed offset press 01 from a printing process currently running in this printing press to a subsequent printing process, the left column being the 2nd the relevant print image on a print sheet 02 a currently running printing process (order A) and in the right column the 2nd the corresponding printed image on a printed sheet 02 of a new subsequent printing process (order B) is shown. So it shows 2nd the starting situation and in comparison the desired new situation.

The following is a method for setting a color profile in a sheetfed offset printing press 01 with which the sheetfed offset printing press 01 from a printing process currently running in this printing press to a subsequent printing process, in particular when using high-priced printing materials, e.g. B. of metal sheets, can be changed over inexpensively and quickly. In this sheetfed offset press 01 are multiple press sheets 02 - hereinafter briefly as a bow 02 referred to - one after the other along a transport path through this sheet-fed offset printing machine, these sheets 02 be colored with at least one printing ink on the transport route. For coloring the sheets 02 has the sheetfed offset press 01 at least one inking unit providing the printing ink in question 04 with several each across the transport path of the sheets 02 lined up color zones, one in each of these color zones by a control unit 16 adjusted or at least adjustable ink metering element for metering the in the respective ink zone on the sheet 02 amount of ink to be applied is arranged. The control unit 16 by setting the respective ink metering elements of the inking unit in question 04 that for this inking unit 04 applicable color profile. The setting of the respective ink metering elements of the inking unit in question 04 takes place with the aim that the inking unit in question 04 the bow 02 in a production run of the sheetfed offset press 01 each with a target coloring. To achieve this goal, the control unit 16 the respective one for the inking unit in question 04 color profile applicable to its target coloring based on several of these sheets 02 recorded color density values and / or colorimetric values and based on a recorded image of one on the respective sheet 02 applied printed image each iteratively. The respective color density values and / or the respective colorimetric values and also the respective image from the relevant printed image applied to the respective sheet are in each case checked with at least one with the control unit 16 at least technically connected in the sheetfed offset printing press 01 arranged detection device 17th detected.

• Bis zum Beginn des verkaufsfähig bedruckte Bogen 02 produzierenden Fortdrucks dieser Bogenoffsetdruckmaschine 01 werden nacheinander mehrere aus unterschiedlichen Mengen von Makulaturbogen und/oder Gutbogen zusammengesetzte Pakete von Bogen 02 entlang des Transportweges durch diese Bogenoffsetdruckmaschine 01 geführt. Dabei werden als Makulaturbogen jeweils vorbedruckte Bogen 02 jeweils mit einem vom im Fortdruck der Bogenoffsetdruckmaschine 01 abweichenden Druckbild aus einem vorherigen Druckauftrag und als Gutbogen jeweils unbedruckte Bogen 02 verwendet.

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

• Until the beginning of the salable printed sheet 02 producing production of this sheetfed offset printing machine 01 are successively several packages of sheets composed of different amounts of waste sheets and / or good sheets 02 along the transport route through this sheetfed offset printing machine 01 guided. Pre-printed sheets are used as waste sheets 02 each with one of them in the production of the sheetfed offset press 01 deviating print image from a previous print job and as unprinted sheets 02 used.

There are now at least the following packages of sheets 02 successively through this sheetfed offset printing machine 01 A sheet of metal sheet is preferably used as the waste sheet and / or as the 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 a third package of sheets 02 with several waste sheets and each with at least one good sheet. The waste sheets of the first package and the one or more sheets of the second package are each inked in accordance with the color profile that does not correspond to the target color, from 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 sheetfed offset press 01 each goes out, so with a color profile, which z. B. the coloring of sheets 02 one of the print jobs that preceded the print job currently being set corresponds to.

During the mentioned packages of sheets 02 one after the other through the sheetfed offset printing machine 01 the control unit recognizes 16 the at least one good sheet of the second package either according to a z. B. by an operator of the sheetfed offset press 01 manual entry made with the control unit 16 control device connected by data technology 19th or in a higher technical level automatically as a good sheet. With the recognition of the good sheet or sheets, the control unit 16 a respective position of several color measuring fields, each position of these color measuring fields in each of the color zones of the inking unit in question 04 is arranged. Following the second through the sheetfed offset press 01 guided package of bow 02 detects the control unit 16 the others with this sheetfed offset press 01 guided arch 02 by means of the relevant detection device 17th their respective color density values and / or colorimetric values at the respectively defined positions of the color measuring fields.

The control unit also detects 16 with the relevant detection device 17th at the latest when the bow begins 02 of the second package of those through the sheetfed offset press 01 guided arch 02 an image of each on the respective sheet 02 applied printed image. The control unit also saves 16 with the recognition of the one or more sheets of the second package, a master image, the master image being at least one contour of the sheet-fed offset printing press 01 on the bow 02 has to be created print image. The control unit 16 compares the respective with the relevant detection device 17th captured images of each following the second package by the sheetfed offset press 01 guided arch 02 each with the master image, the control unit 16 this other bow 02 checks for the presence of a print image corresponding to the master image. The control unit evaluates 16 arc 02 with a print image corresponding to the master image as a good sheet and sheet 02 with a printed image that does not correspond to the master image as a waste sheet. The control unit 16 then leaves sheets evaluated as waste sheets 02 in the formation of the respective color profile by the control unit 16 each after the second by the sheetfed offset press 01 guided package of bow 02 is set, not taken into account, so that only sheets rated as good sheets 02 be used to form the respective new color profile to be set. As a result, the control unit 16 starting with the bow 02 of the third package the respective color profile on the inking unit in question 04 on the basis of the respective color density values and / or colorimetric values recorded in each case by good sheets until they match the respective color profile applicable for the target coloring.

It is preferably provided that the control unit 16 at least of the one or more sheets of the second package stores the respective image of the print image in question and on the with the control unit 16 connected display device 23 displays.

In a preferred embodiment, the control unit determines 16 from several each at the same positions of the respective good sheets of the third package by means of the respective detection device 17th recorded color density values and / or colorimetric values each have a mean value and uses these mean values for setting the respective color profile.

The master image can be from the control unit 16 be created such that the control unit 16 the resolution of the relevant original captured image of the or the good sheet of the second package, given by its amount of pixels, is reduced and the remaining amount of pixels is used as an image signature representing the master image, the control unit using the image signature representing the master image to check for the presence of one Master image corresponding print image after the creation of the master image along the transport route through the sheet-fed offset printing machine 01 guided arch 02 used.

In the event that to capture the respective image from the relevant to the respective sheet 02 applied print image a detection device having a plurality of color channels 17th is used forms the control unit 16 the respective image signature of the master image z. B. separately for each color channel of the detection device 17th and uses the image signature of the master image formed in color channels 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 e.g. B. uses a digital preview image from a prepress.

In addition, it can be provided that the control unit 16 after formation of the master image for subsequent through this sheetfed offset printing machine 01 guided arch 02 sets an axial register and / or a circumferential register and / or a color register.

When retrofitting or proofing the sheetfed offset press 01 is carried out according to the previously described method, the control unit 16 usually the respective color profile, which at the end of the last third package of sheets 02 is set 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 press 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 lead waste for basic coloring of the sheets 02 after the printing ink has entered the inking unit concerned 04 . For the third packages z. B. 10 to 15 sheets 02 used, the control unit 16 only improves the respective color profile using the sheets identified as good sheets in each of these third packages until the sheets are colored 02 within the previously defined permissible tolerance limits corresponds to the color profile applicable for the target coloring. The color profile that applies to the target coloring is therefore determined by the control unit 16 on the basis of the recognized good sheets serving as support points in each case gradually set and / or adjusted.

The method proposed here takes into account, on the one hand, that there is a reaction to an inking unit 04 changed setting of ink zone openings on a sheetfed offset press 01 with this changed setting colored bow 02 detected color density values cannot change suddenly or abruptly, but that these color density values only reach a new stable state after a certain time, ie after a certain machine running time. On the other hand, the method proposed here succeeds in setting the color profile applicable for the target coloring with only the smallest possible number of high-priced sheets 02 to reach.

The proposed method for setting a color profile in a sheetfed offset printing press 01 used for a retrofit after an order change or when the sheetfed offset press in question is printed 01 Pre-printed waste sheets and unprinted good sheets, with at least one good sheet being repeated, that is to say in the form of a plurality of successive packages, in each case after a plurality of waste sheets, by the sheet-fed offset printing machine 01 and the waste sheets and good sheets are in each case in particular by means of at least one inking unit each having a plurality of color zones 04 be inked, the inked sheets in the sheetfed offset printing machine 01 according to a z. B. by an operator of the sheetfed offset press 01 manual entry made on a control device 19th the relevant sheetfed offset printing machine 01 or automatically z. B. by means of image recognition as such, ie recognized as a good sheet and the setting of the color profile by means of an inking unit in question 04 acting color regulator 24th after recording and evaluating the respective inking alone, ie only the recognized good sheet is carried out. Further details of this method have been described previously, e.g. B. that the detection of the respective inking of the waste sheets and good sheets are in particular inline, ie in the sheet-fed offset printing machine in question 01 with a z. B. designed as a camera detection device 17th takes place and / or that the automatic recognition of the good sheets takes place by means of an image recognition and / or 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 sheets.

3rd once again illustrates the timing of the proposed method for setting a color profile in a sheetfed offset press to be set for a new print job 01 over a timeline running from left to right t . It is believed that at a time t0 retrofitting the relevant sheetfed offset press 01 after a job change or the printing of a new print job begins.

The proposed method starts with z. B. on a feeder of the sheetfed offset press 01 Already provided waste sheets from at least one previous printing process, each provided with a print image, ie respectively printed and not intended for sale, by the sheet-fed offset printing machine 01 guided and by the at least one inking unit 04 this sheetfed offset press 01 be colored. This is a first package P1 of bow 02 with z. B. 40 to 50 waste sheets, which are successively by this sheetfed offset printing machine 01 be performed. At the time t0 is on the relevant inking units 04 a color profile that no longer corresponds to the previous print job, but in any case has not yet been set to a color profile corresponding to the target color of the new print job. During the the first package P1 of bow 02 inking phase of the sheetfed offset press 01 becomes an inflow of printing ink to the respective inking unit 04 usually not reduced or stopped.

At the time t1 are all waste sheets of the first package P1 of bow 02 through the sheetfed offset press 01 been led. This is the first package P1 of bow 02 inking phase of the sheetfed offset press 01 completed. From the time t1 will be at least one blank sheet as a second package P2 of bow 02 e.g. B. on the feeder of the sheetfed offset press 01 provided and then for its coloring by the sheet-fed offset printing machine 01 guided. Either according to one by an operator of the sheetfed offset press 01 manual input on one with this sheetfed offset printing machine 01 at least technically connected control device 19th or in each case automatically the good sheet or sheets are recognized as such. With the recognition of the or the good sheet of the second package P2 is with respect to the bow 02 of the new print job to be processed also specifies a respective position of several color measuring fields, at which others are set by the sheetfed offset printing press 01 guided arch 02 by means of one in this sheetfed offset printing machine 01 arranged and with a control unit 16 this sheetfed offset press 01 at least data-related detection device 17th their respective color density values and / or colorimetric values are recorded. At the latest from the time t1 is with the aforementioned or another detection device 17th of those through this sheetfed offset press 01 guided arch 02 of the second package P2 and all others through the sheetfed offset press 01 guided arch 02 an image of each on the respective sheet 02 applied printed image captured. With the recognition of the or the good sheet of the second package P2 is also in a storage facility 18th the control unit 16 a master image is stored, the master image being at least one contour of the sheet-fed offset printing press 01 according to the new print job to be processed on the sheet 02 has to be created print image. From the time t2 compares the control unit 16 the respective with the relevant detection device 17th captured images of those following the second package P2 each through the sheetfed offset press 01 guided arch 02 each with the stored master image, the control unit 16 this other bow 02 checks for the presence of a print image corresponding to the master image. In this test, the control unit evaluates 16 arc 02 with a print image corresponding to the master image as a good sheet and sheet 02 with a printed image that does not correspond to the master image as a waste sheet. The control unit 16 starts at the time t2 also, the respective color profile on the inking unit in question 04 on the basis of the respective color density values and / or colorimetric values recorded by the good sheet, iteratively until they match the respective color profile applicable for the target coloring, starting from the point in time t2 several packages P3n each consisting of several waste sheets and at least one good sheet through this sheetfed offset printing machine 01 be performed. When forming the respective color profile, that of the control unit 16 each after the second by the sheetfed offset press 01 guided package P2 of bow 02 , i.e. from the time t2 is set, the control unit 16 She considered sheets as waste sheets 02 disregarded. Only that from the control unit 16 sheets recognized as good sheets 02 serve as support points for the gradual adjustment of the respective color profile applicable for the target coloring.

After all bow 02 of the third packages P3n one after the other through the sheetfed offset printing machine 01 and the respective color profile on the basis of the sheets recognized as good sheets 02 has been set in better and better correspondence with the color profile applicable for the target coloring, at the time t3 from the production of the sheetfed offset press 01 assumed and the control unit 16 turns on and / or the color slider 24th in a corresponding operating mode.

Reference list

01

Sheet printing machine

02

Printed sheet, sheet

03

Printing unit

04

Inking unit

05

-

06

Paint box

07

Color ductor

08

Ink transfer roller

09

Inking roller

10th

-

11

Forme cylinder

12th

Transfer cylinder

13

Impression cylinder

14

Color lifter

15

-

16

Control unit, control device

17th

Detection device

18th

Storage device

19th

Control device

20

-

21

Control center

22

Communication network

23

Display device

24th

Color slider

P1

first package of sheets ( 02 )

P2

second package of sheets ( 02 )

P3n

third package of sheets ( 02 )

t

time beam

t0

time

t1

time

t2

time

t3

time

T

Direction of transport

QUOTES INCLUDE IN THE DESCRIPTION

This list of documents listed by the applicant has been generated automatically and is only included for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• WO 2010/091947 A1 [0002]
• DE 3707695 A1 [0003]
• DE 102008029998 A1 [0014]

Claims (13)

Method for setting a color profile in a sheet-fed offset printing press (01), in which pre-printed waste sheets and unprinted positive sheets are used when converting after a change of order or when the sheet-fed offset printing press (01) in question is printed, in which at least one good sheet is repeated by the customer after several waste sheets Sheet-fed offset printing machine (01) is guided and the waste sheets and good sheets are each inked by means of at least one inking unit (04) each having a plurality of ink zones, in which the inked-good sheets in the sheet-fed offset printing machine (01) according to a manual one carried out by an operator of the sheet-fed offset printing machine (01) Input on an operating device (19) or in each case automatically recognized as such and the color profile is set by means of a color controller (24) after a detection and evaluation of the respective inking exclusively of the recognized good sheets. Procedure according to Claim 1 , characterized in that the detection of the respective coloring of the waste sheets and good sheets takes place inline and / or with a detection device (17) designed as a camera and / or that the automatic detection of the good sheets takes place by means of image recognition and / or that the evaluation of the the recognized good sheets are colored in each case on the basis of color density values and / or colorimetric values recorded on these good sheets. Method for setting a color profile in a sheet-fed offset printing machine (01), wherein a plurality of sheets (02) are guided in succession along a transport path through this sheet-fed offset printing machine (01), these sheets (02) being inked on the transport path with at least one printing ink, 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), wherein in each of these ink zones one ink metering element set or at least adjustable by a control unit (16) for metering the ink in of the relevant ink zone, the amount of printing ink to be applied to the sheets (02) is arranged, the control unit (16) setting the color profile applicable to this inking unit (04) by adjusting the respective ink metering elements of the inking unit (04), the inking unit in question ( 04) the bow (02) in egg When the sheetfed offset printing press (01) is being printed, each inked with a target inking, the control unit (16) coloring the respective color profile applicable to the respective inking unit (04) during its target inking on the basis of color density values and / or colorimetric values recorded on several of these sheets (02) and on the basis of a captured image of a printed image applied to the respective sheet (02), iteratively sets the respective color density values and / or the respective colorimetric values and also the respective image of the respective printed image applied to the respective sheet (02) with at least a detection device (17), which is connected to the control unit (16) for data processing purposes and is directed towards the transport path of the respective sheet (02), characterized in that a. that until the start of the printing of this sheet-fed offset printing machine (01), several packages of sheets (02) composed of different quantities of waste sheets and / or good sheets are successively guided along the transport path through this sheet-fed offset printing machine (01), pre-printed sheets (02) being used as waste sheets In each case, a sheet (02) that is unprinted from the print run of the sheet-fed offset printing machine (01) from a previous print job and as a good sheet can be used, with at least the following packages of sheets (02) being passed through this sheet-fed offset printing machine (01) in succession: aa first package of sheets (02) consisting of several waste sheets, from a second package consisting of at least one good sheet, ac at least a third package of sheets (02) each with several waste sheets and each with at least one good sheet, ad being the waste sheets of the first package and the one or more sheets of the second Pak etes are colored according to the color profile that does not correspond to the target coloring, from which the control unit (16) assumes when setting the color profile of the at least one inking unit (04), b. that the control unit (16) recognizes the at least one good sheet of the second package as a result of manual input on an operating device (19) connected to the control unit (16) for data processing purposes, or automatically as a good sheet, and a respective position of a plurality of color measurement fields with the recognition of the good sheet or sheets determines, each position of each of these color measurement fields being arranged in one of the color zones of the relevant inking unit (04), c. that the control unit (16) in connection with the second packet of sheets (02) guided by the sheet-fed offset printing machine (01) in the case of others the sheet-fed offset printing machine (01) guides the sheet (02) by means of the relevant detection device (17) at the respective fixed positions of the color measuring fields, their respective color density values and / or colorimetric values, i. 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) guided by the sheet-fed offset printing machine (01) each have an image of the printed image applied to the respective sheet (02) recorded, e. that the control unit (16) stores a master image with the recognition of the one or more good sheets of the second package, the master image having at least one contour of the printed image to be produced on the sheet (02) by the sheet-fed offset printing press (01), f. that the control unit (16) compares the respective images of the sheets (02) fed through the sheet-fed offset printing press (01) following the second package with the master image, the control unit (16) comparing these further images Checks sheets (02) for the presence of a print image corresponding to the master image, the control unit (16) evaluating sheets (02) with a print image corresponding to the master image as a good sheet and sheets (02) with a print image not corresponding to the master image as a waste sheet , wherein the control unit (16) evaluates sheets (02) as waste sheets when forming the respective color profile, which is set by the control unit (16) in each case following the second packet of sheets (02) guided by the sheet-fed offset printing machine (01), disregarded, g. that the control unit (16), starting with the sheets (02) of the third package, iteratively applies the respective color profile on the relevant inking unit (04) on the basis of the respective color density values and / or colorimetric values recorded by the good sheets until they match the respective one for the target coloring Color profile. Procedure according to Claim 3 characterized in that the control unit (16) stores the respective image of the relevant print image at least of the one or more good sheets of the second package and displays it on a display device (23) connected to the control unit (16). Procedure according to Claim 3 or 4th , characterized in that the control unit (16) determines a mean value from a plurality of respectively at the same positions of the respective good sheets of the third package, in each case by means of color density values and / or colorimetric values recorded with the relevant detection device (17), and these mean values for setting the respective color profile used. Procedure according to Claim 3 or 4th or 5 , 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 of the relevant original captured image or the good sheet of the second package given by its number of pixels and the remaining amount of pixels used as an image signature representing the master image, the control unit (16) using the image signature representing the master image to check for the presence of a print image corresponding to this master image on sheets (02) guided along the transport path after the creation of the master image along the transport path through the sheet-fed offset printing machine (01) . Procedure according to Claim 6 , characterized in that a detection device (17) having a plurality of color channels is used to detect the respective image from the relevant print image applied to the respective sheet (02), the control unit (16) separating the respective image signature of the master image separately for each color channel of the detection device (17) and used to check the existence of a print image corresponding to this master image. Procedure according to Claim 3 or 4th or 5 or 6 or 7 , characterized in that the master image is formed from the respective image of the good sheet or sheets of the second package or that a digital preview image from a prepress is used as the master image. Procedure according to Claim 3 or 4th or 5 or 6 or 7 or 8th , characterized in that the control unit (17), after forming the master image, sets an axial register and / or a circumferential register and / or a color register for sheets (02) subsequently guided through this sheet-fed offset printing press (01). Procedure according to Claim 3 or 4th or 5 or 6 or 7 or 8th or 9 , characterized in that the control unit (16) sets the respective color profile, which is set at the end of the last third packet of sheets (02), on the relevant inking unit (04) as the color profile applicable for the production run. Procedure according to Claim 3 or 4th or 5 or 6 or 7 or 8th or 9 or 10th , characterized in that 40 to 50 waste sheets are used for the first package. Procedure according to Claim 3 or 4th or 5 or 6 or 7 or 8th or 9 or 10th or 11 , characterized in that 10 to 15 sheets (02) are used for the third packages. Procedure according to Claim 1 or 2nd or 3rd or 4th or 5 or 6 or 7 or 8th or 9 or 10th or 11 or 12th , characterized in that a sheet of metal is used as the waste sheet and / or as the good sheet.

Images