EP0421003A1 - Méthode pour contrôler l'apport d'encre dans une machine d'impression - Google Patents

Méthode pour contrôler l'apport d'encre dans une machine d'impression Download PDF

Info

Publication number
EP0421003A1
EP0421003A1 EP89118248A EP89118248A EP0421003A1 EP 0421003 A1 EP0421003 A1 EP 0421003A1 EP 89118248 A EP89118248 A EP 89118248A EP 89118248 A EP89118248 A EP 89118248A EP 0421003 A1 EP0421003 A1 EP 0421003A1
Authority
EP
European Patent Office
Prior art keywords
color
vectors
values
individual
vector
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP89118248A
Other languages
German (de)
English (en)
Other versions
EP0421003B1 (fr
Inventor
Hans Joachim Dr. Six
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Grapho Metronic Mess und Regeltechnik GmbH and Co KG
Original Assignee
Grapho Metronic Mess und Regeltechnik GmbH and Co KG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Grapho Metronic Mess und Regeltechnik GmbH and Co KG filed Critical Grapho Metronic Mess und Regeltechnik GmbH and Co KG
Priority to DE58908748T priority Critical patent/DE58908748D1/de
Priority to EP19890118248 priority patent/EP0421003B1/fr
Publication of EP0421003A1 publication Critical patent/EP0421003A1/fr
Application granted granted Critical
Publication of EP0421003B1 publication Critical patent/EP0421003B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41F—PRINTING MACHINES OR PRESSES
    • B41F33/00—Indicating, counting, warning, control or safety devices
    • B41F33/0036—Devices for scanning or checking the printed matter for quality control
    • B41F33/0045—Devices for scanning or checking the printed matter for quality control for automatically regulating the ink supply

Definitions

  • the invention relates to a method for controlling the ink flow in a printing press, in each of which a color location of a test area of a proof or proof set (hereinafter referred to as a template) and during setup and / or during printing (for the sake of simplicity hereinafter referred to as printing). is determined by means of a color measuring device and the measured values are each transformed into a color vector corresponding to the color of the test area in a selected color space, preferably the color space L *, U *, V * or L * +, U *, V * recommended by the CIE .
  • the object of the invention is to provide a technically less complex method for controlling the color control of an offset printing press, which enables setup and production without having to resort to extensive memory data so that the color match between the original and the print is limited to an accuracy limited by interference can be achieved in the shortest possible time.
  • the desired coloring of multicolored superimposed prints in each color zone is as usual achieved that the ink zone control elements are adjusted accordingly.
  • a printed control bar with corresponding grid fields and / or solid color fields of the individual colors arranged transversely or longitudinally to the paper running direction of the printing machine certain colorations then result, the color density or color location of which can be measured in order to carry out the control process in the manner according to the invention.
  • Legal relationships can be demonstrated between the measured values for the individual colors and the overprinting, which can be represented as color locations in a color space, which, however, do not have the character of clear mathematical equations, but are subject to fluctuations due to the random influences inherent in the printing process, i.e. for model considerations - expressed mathematically - contain random quantities.
  • a frequency distribution can then be determined, the parameters of which can be used to describe the relationships.
  • An auxiliary coordinate system is developed from the individual color vectors, the axes of which lie in the directions of the individual color vectors.
  • the color vector of the current overprint is broken down into vector components on the axes of this auxiliary coordinate system so that it represents their sum. These vector components are merely arithmetic variables in the form of apparent color vectors which, in additive color mixing, result in the test field color.
  • the color vector of the test field of the template is broken down into such sham color vectors on the axes of the auxiliary coordinate system.
  • a linear relationship is assumed between the amounts of the vector components of the color vector of the test field and those of the corresponding individual color vectors, so that a single color vector to be assigned to the components of the test field color vector can be calculated for each color from the value pairs of these quantities determined for printing.
  • a fictitious individual color vector belonging to the test field color of the proof is determined from the ratios of the amounts of these apparent color vectors and the individual color vector lying in the same axis.
  • the individual color vectors of the template determined in this way, or the color locations defined by them, would now again refer to the originally selected color space, which would have resulted in the test field color of the template. If one were to change the ink zone control elements of the printing press from those positions which had been selected for printing and which correspond to the color locations used at the outset, to those positions which correspond to the new color locations obtained in the manner explained above, then the test field color of the new print would have to be be identical to that of the template.
  • the color locus of the printed multicolored test fields becomes the control variable, while the reference variable is formed by the color locus of the multicolored test field of the template.
  • the regulation is carried out until a predetermined tolerance is undershot, which is generally determined by unavoidable process fluctuations in the printing process. Since each color location of a multicolored overprint in offset printing e.g. realized via independent inking units, the colors of the color fields of the individual colors or the apparent colors that add up to the colorations of gray fields, for example, are introduced as auxiliary variables, and in contrast to the known regulation of the color densities of printed color fields of the individual colors, in which the As a rule, the control variable has a constant value, the value of the auxiliary control variable is newly determined after each control step.
  • the method described above can be used for several selected or for all color zones across the machine width. But you can also simplify the effort if you only use the auxiliary coordinate system for a "pattern zone" is constructed and the color vectors of the respective test fields measured for other zones are broken down into additive vector components on the axes of this one auxiliary coordinate system and calculated fictitious individual color vectors for the respective test field of the other color zones from their relationship to the corresponding vector components of the pattern zone, with the help of these then the correction values for the color control elements of the respective color zones are determined.
  • Another embodiment of the invention consists in that the decomposition vectors of the color vector of the test field color are not applied to the axes of the auxiliary coordinate system derived from the printed individual colors of the test field of a pattern zone, but instead color density values of the basic colors, which were determined on printed single color fields of the basic color of the test field .
  • This variant is based on the experience that the ratio of the density values of each primary color of the two compared test fields is approximately the same within certain limits to the ratio of the length of the color vectors of these primary colors.
  • the color density is not a vectorial quantity, it is applied in the direction of the respective individual color vector of the pattern field, that is to say on the axis of the auxiliary coordinate system defined by it.
  • an individual color vector can be calculated back for the test area under consideration.
  • color vectors can also be calculated back in a corresponding manner.
  • a variant of this embodiment is that instead of measured color density values, this corresponds to the scaling of the axes of the auxiliary coordinate system
  • the numerical setting values of the relevant color zone setting elements are plotted on the axes, an at least approximately proportional relationship between these setting values and the color density values being assumed.
  • a single color vector can be calculated from the ratio of the color density setting values and the single color vector (from the pattern zone).
  • test field In the interest of good results, it is advisable to print the test field with a mixed color in which the individual printing inks used are represented so strongly that measurement errors are kept as small as possible. To meet these conditions, it is advisable to choose a standard color according to DIN 6169 for the color of the test field.
  • the settings of the color zone control elements on the basis of the determined correction values are expediently carried out according to an algorithm which has proven itself for the regulation of the color density of printed test fields.
  • the values of the introduced auxiliary control variables converge except for the fluctuations currently caused by the printing method.
  • the stable print can be achieved on average according to predetermined values for the color location of any measuring fields within the tolerances of the printing process, it being particularly advantageous that one does not have to resort to table values or general calculations that require considerable memory and computing capacity, and that usually lead to such large deviations in the result that intervention must be carried out by trained personnel, but goes directly back to the currently prevailing printing conditions and queries the real printing result, for which only a comparatively small effort is required.
  • the method according to the invention corrects itself; Setup and production printing need not be treated differently, since the control algorithms apply to both.
  • the test field of the proof is a gray balance field, the color of which is to be achieved during printing by overprinting the basic colors cyan (C), magenta (M) and yellow (Y).
  • Fig. 1 shows an example of a superimposed printing of triangular surfaces of these primary colors C, M and Y, which overlap in the middle area and which result in a shade of gray with correct surface coverage.
  • the test field of the original, the test field of the current print and the three primary colors belonging to the latter are measured, for example in the form of the standard color values X, Y and Z, which are then converted into color locations of a suitable color system, for example, according to known CIE transformation equations L *, U *, V * systems.
  • the following table 1 shows examples of such measured values and color locus values which have been obtained for the D65 light type and 2-degree observer, 45/0 degree geometry.
  • a color control bar can be installed to control the printing of a print run, preferably in each color zone, among others. contains the same gray balance field as the proof and additionally the associated color fields for the chromatic colors cyan, magenta and yellow, although these color fields do not have to be arranged in the same way as is only exemplarily illustrated in FIG. 1.
  • the printed measuring fields of the color control bar are measured in all color zones in the manner explained above using a color measuring device. The further calculations are then usually done automatically. To simplify the considerations made here, however, only a single color zone is envisaged, and the following considerations can be applied analogously to all other color zones.
  • the color vector G v is the color location of the test field (for example a gray balance field) of the original in the L *, U *, V * system indicates.
  • the color vector G d can be seen, which characterizes the color location of the comparable test field of the printed sheet in this color space.
  • the three color vectors for the three co-printed primary colors cyan, magenta and yellow are shown and designated FC d (color cyan printed sheet) FM d and FY d .
  • an auxiliary coordinate system is now constructed according to the invention in such a way that the direction of these individual color vectors define the axes of the auxiliary coordinate system: These axes are designated FC, FY and FM.
  • the gray vector G d of the printed sheet is broken down into three additive components corresponding to these axes, which are designated GC d , GM d and GY d in FIG. 2.
  • the gray vector of the template is broken down into three additive components lying on these axes, which are designated GC v , GM v and GY v .
  • the auxiliary coordinate system just described takes into account the current pressure conditions, since it is defined by the vectors of the individual colors currently also printed. It should also be pointed out that the decomposition of the color vectors into additive components of this auxiliary coordinate system is only a conceptual construction in which these addition components are used as a computational auxiliary quantity without reference to the physical color decomposition, since it is generally not the case when printing colors one on top of the other additive, but the print is the so-called autotypical color mixture.
  • the invention is now based on the idea that the same considerations apply to the decomposition of the original gray color vector as for the decomposition of the print gray color vector, and that between the amounts of the vector components of the Gray color vectors and those of the associated single color vectors exist legally.
  • linearity can be assumed, which means proportionality for the dependence of the amounts of the individual color vectors on the associated components of the gray color vectors.
  • FC d GC d for example, FC d GC d and thus FC b GC v .
  • the ratio of the additive vector components GC v / GC d in each axis of the auxiliary coordinate system must also apply to the current color vectors lying in the relevant axis, so that the color vector of the pressure lying in the relevant axis of the auxiliary coordinate system, for example FC d , with the help of this ratio, would have to have it calculated back into a color vector of the original which corresponds to a single printing ink which, together with the other printing inks determined in the same way, would have produced exactly the gray of the original.
  • fictitious original single color vectors The back-calculated individual color vectors for the proof are referred to here as fictitious original single color vectors, since they are initially not yet known and are only determined as fictitious single color vectors from which the color vectors for original and print and the known print single color vectors are compared one has to imagine the gray of the original.
  • the fictitious color vectors determined in this way define color locations in the original L *, U *, V * color space, to which we now go back, which correspond to the individual colors that, when combined, should result in the desired gray of the original.
  • Table 2 shows numerical examples for the just explained determination of the fictitious color vectors for the original gray.
  • the color zone control elements of the machine are updated according to known relationships , and with the resulting print result, the same procedure is used again.
  • the fictitious color vectors FC b , FM b and FY b are used as control variables for the control of the ink supply, specifically as auxiliary control variables in contrast to the actual control variable "color location".
  • the color zone control elements are then controlled as if the above-mentioned values were current target values for the coloring in the control sense.
  • an algorithm is used to determine the settings of the color zone control elements, as has proven itself in regulating the color density.
  • the color difference between the latest state of the color location of the gray field of the new measuring sheet and that of the gray field of the original falls below a certain tolerance value, which is due to the influences mentioned at the outset and does not allow any further accuracy. It is essential for the described method that the color difference between the color location of the test field of the original and that of the currently printed test field decreases with each further step and the value of the command variable stabilizes within the tolerance mentioned to an expected value. Inaccurate intermediate values are of minor importance due to the convergence of this iterative process.

Landscapes

  • Engineering & Computer Science (AREA)
  • Quality & Reliability (AREA)
  • Inking, Control Or Cleaning Of Printing Machines (AREA)
  • Spectrometry And Color Measurement (AREA)
EP19890118248 1989-10-02 1989-10-02 Méthode pour contrôler l'apport d'encre dans une machine d'impression Expired - Lifetime EP0421003B1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
DE58908748T DE58908748D1 (de) 1989-10-02 1989-10-02 Verfahren zur Steuerung der Farbführung bei einer Druckmaschine.
EP19890118248 EP0421003B1 (fr) 1989-10-02 1989-10-02 Méthode pour contrôler l'apport d'encre dans une machine d'impression

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP19890118248 EP0421003B1 (fr) 1989-10-02 1989-10-02 Méthode pour contrôler l'apport d'encre dans une machine d'impression

Publications (2)

Publication Number Publication Date
EP0421003A1 true EP0421003A1 (fr) 1991-04-10
EP0421003B1 EP0421003B1 (fr) 1994-12-07

Family

ID=8201973

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19890118248 Expired - Lifetime EP0421003B1 (fr) 1989-10-02 1989-10-02 Méthode pour contrôler l'apport d'encre dans une machine d'impression

Country Status (2)

Country Link
EP (1) EP0421003B1 (fr)
DE (1) DE58908748D1 (fr)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4311132A1 (de) * 1992-04-28 1993-11-04 Heidelberger Druckmasch Ag Verfahren zur farbregelung/-steuerung in einer druckmaschine
EP0632645A1 (fr) * 1993-06-29 1995-01-04 Schablonentechnik Kufstein Aktiengesellschaft Procédé de reproduction de motifs et pochoir pour ce dernier
EP0668164A1 (fr) * 1994-01-31 1995-08-23 Maschinenfabrik Wifag Acquisition des données de qualité dans une machine rotative offset pour feuilles
EP0676285A1 (fr) * 1994-01-31 1995-10-11 Maschinenfabrik Wifag Gestion des couleurs dans une machine rotative offset pour feuilles
DE102011015306A1 (de) * 2011-03-29 2012-10-04 Heidelberger Druckmaschinen Ag Verfahren zur Graubalancekorrektur eines Druckprozesses
CN103042853A (zh) * 2013-01-21 2013-04-17 上海紫恩数码科技有限公司 一种专色模拟的方法
AT512440A1 (de) * 2012-01-20 2013-08-15 Ait Austrian Inst Technology Farbtreueprüfung
US8537420B2 (en) 2010-03-24 2013-09-17 Heidelberger Druckmaschinen Ag Method for gray balance correction of a printing process

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3707027A1 (de) * 1987-03-05 1988-09-15 Deutsche Forsch Druck Reprod Verfahren zur steuerung der farbgebung im mehrfarbendruck
DE3714179A1 (de) * 1987-04-29 1988-11-17 Forschungsgesellschaft Fuer Dr Verfahren zur steuerung der farbgebung im mehrfarbendruck
EP0321402A1 (fr) * 1987-12-16 1989-06-21 GRETAG Aktiengesellschaft Procédé de commande ou du réglage de l'encrage d'une presse à imprimer
EP0228347B1 (fr) * 1985-12-10 1989-10-25 Heidelberger Druckmaschinen Aktiengesellschaft Procédé de commande de l'alimentation en encre pour une machine à imprimer, dispositif d'impression équipé de manière correspondante et dispositif de mesure pour un tel appareil d'impression

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0228347B1 (fr) * 1985-12-10 1989-10-25 Heidelberger Druckmaschinen Aktiengesellschaft Procédé de commande de l'alimentation en encre pour une machine à imprimer, dispositif d'impression équipé de manière correspondante et dispositif de mesure pour un tel appareil d'impression
DE3707027A1 (de) * 1987-03-05 1988-09-15 Deutsche Forsch Druck Reprod Verfahren zur steuerung der farbgebung im mehrfarbendruck
DE3714179A1 (de) * 1987-04-29 1988-11-17 Forschungsgesellschaft Fuer Dr Verfahren zur steuerung der farbgebung im mehrfarbendruck
EP0321402A1 (fr) * 1987-12-16 1989-06-21 GRETAG Aktiengesellschaft Procédé de commande ou du réglage de l'encrage d'une presse à imprimer

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4311132A1 (de) * 1992-04-28 1993-11-04 Heidelberger Druckmasch Ag Verfahren zur farbregelung/-steuerung in einer druckmaschine
EP0632645A1 (fr) * 1993-06-29 1995-01-04 Schablonentechnik Kufstein Aktiengesellschaft Procédé de reproduction de motifs et pochoir pour ce dernier
US5553161A (en) * 1993-06-29 1996-09-03 Schablonentechnik Kufstein Aktiengesellschaft Copy reproduction apparatus for screen printing with color correction
EP0668164A1 (fr) * 1994-01-31 1995-08-23 Maschinenfabrik Wifag Acquisition des données de qualité dans une machine rotative offset pour feuilles
EP0676285A1 (fr) * 1994-01-31 1995-10-11 Maschinenfabrik Wifag Gestion des couleurs dans une machine rotative offset pour feuilles
US5730470A (en) * 1994-01-31 1998-03-24 Maschinenfabrik Wifag Quality data collection in rotary offset printing of single editions
US8537420B2 (en) 2010-03-24 2013-09-17 Heidelberger Druckmaschinen Ag Method for gray balance correction of a printing process
DE102011012806B4 (de) 2010-03-24 2022-07-07 Heidelberger Druckmaschinen Ag Graubalancekorrektur eines Druckverfahrens
DE102011015306A1 (de) * 2011-03-29 2012-10-04 Heidelberger Druckmaschinen Ag Verfahren zur Graubalancekorrektur eines Druckprozesses
US8810857B2 (en) 2011-03-29 2014-08-19 Heidelberger Druckmaschinen Ag Method and printing system for gray balance correction of a printing process, computer program product and computer program storage device
AT512440A1 (de) * 2012-01-20 2013-08-15 Ait Austrian Inst Technology Farbtreueprüfung
AT512440B1 (de) * 2012-01-20 2014-08-15 Ait Austrian Inst Technology Farbtreueprüfung
CN103042853A (zh) * 2013-01-21 2013-04-17 上海紫恩数码科技有限公司 一种专色模拟的方法
CN103042853B (zh) * 2013-01-21 2014-07-16 上海紫恩数码科技有限公司 一种专色模拟的方法

Also Published As

Publication number Publication date
EP0421003B1 (fr) 1994-12-07
DE58908748D1 (de) 1995-01-19

Similar Documents

Publication Publication Date Title
EP0255924B1 (fr) Procédé et dispositif pour influencer l'encrage d'une surface encrée dans une machine à imprimer
DE3812099C2 (de) Verfahren zur Farbsteuerung einer Offsetdruckmaschine
EP0196431B1 (fr) Procédé, dispositif de réglage et moyens auxiliaires pour l'obtention d'un résultat d'impression uniforme au moyen d'une machine d'impression offset polychrome fonctionnant suivant le procédé de similigravure
EP0324718B1 (fr) Procédé et dispositif pour régler l'encre dans une machine à imprimer
EP0321402B1 (fr) Procédé de commande ou du réglage de l'encrage d'une presse à imprimer
EP0228347B1 (fr) Procédé de commande de l'alimentation en encre pour une machine à imprimer, dispositif d'impression équipé de manière correspondante et dispositif de mesure pour un tel appareil d'impression
EP0914945B1 (fr) Procédé pour régler l'encrage dans une machine d'impression
DE19515499C2 (de) Verfahren zur simultanen Mehrfarbregelung beim Drucken
DE3028025A1 (de) Verfahren und vorrichtung zur veraenderung des farbflusses, zum unterschiedlichen verstellen einzelner breitenzonen eines farbmessers oder einzelner farbdosierelemente bei druckmaschinen-farbwerken
EP0585740B1 (fr) Méthode pour la commande du processus d'impression dans une presse d'imprimerie à cliché trame en particulier une machine à imprimer offset à feuilles
EP0825023B1 (fr) Procédé pour déterminer des données de reglage pour la commande d'une machine à imprimer
EP0394681B1 (fr) Procédé pour contrôler l'encrage dans une machine d'impression avec limitation de l'épaisseur de la couche d'encre et de l'augmentation de la valeur tonale
EP0421003B1 (fr) Méthode pour contrôler l'apport d'encre dans une machine d'impression
EP0528094A1 (fr) Procédé pour obtenir les données relatives au pourcentage des points de trame
EP0916491B1 (fr) Procédé pour déterminer des gradients colorimétriques
DE19830487B4 (de) Verfahren zur Ermittlung von Flächendeckungen in einem Druckbild
DE4038574C1 (fr)
EP0490093B1 (fr) Procédé de contrôle de l'encrage de produits imprimés
EP0282446B1 (fr) Procédé de réglage continu de l'encrage en impression en creux ou flexographique et machine correspondante
EP1720705B1 (fr) Procede de reglage de la couleur dans des presses d'impression
DE3440706A1 (de) Verfahren zur steuerung oder regelung der farbgebung von druckerzeugnissen
EP0649743A1 (fr) Procédé pour contrôler l'apport de couleur dans une presse fonctionnant suivant le procédé de similigravure
DE10147392B4 (de) Verfahren zum zonenweisen Bedrucken einer Bedruckbahn
DE4410228C2 (de) Verfahren und Vorrichtung zur freiwählbaren Ersetzung des Unbuntanteils im Mehrfarbendruck durch die Druckfarbe Schwarz
DE8414963U1 (de) Kontrolleiste für den Endlosformulardruck

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 19901221

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): CH DE LI

17Q First examination report despatched

Effective date: 19930127

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): CH DE LI

REF Corresponds to:

Ref document number: 58908748

Country of ref document: DE

Date of ref document: 19950119

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20081022

Year of fee payment: 20

Ref country code: CH

Payment date: 20081015

Year of fee payment: 20

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL