Global Patent Index - EP 0649743 B1

EP 0649743 B1 19970409 - Method for controlling the ink supply in a halftone printing machine

Title (en)

Method for controlling the ink supply in a halftone printing machine

Title (de)

Verfahren zur Steuerung der Farbführung einer autotypisch arbeitenden Druckmaschine

Title (fr)

Procédé pour contrÔler l'apport de couleur dans une presse fonctionnant suivant le procédé de similigravure

Publication

EP 0649743 B1 19970409 (DE)

Application

EP 94115333 A 19940929

Priority

  • DE 4335853 A 19931021
  • DE 4431270 A 19940902

Abstract (en)

[origin: EP0649743A1] A method for controlling the ink supply in a halftone printing machine, in particular an offset printing machine, is described. Both in the case of a reference master and on the printed sheet, the standard colour values of the four-colour combined halftone print are determined at test regions located within the subject. For the printing colour black, the infrared colour density is determined within the close infrared. These standard colour values of the four-colour combined print are converted by linear transformation into standard colour values which correspond to the combined printing of only the three chromatic colours. In this case, the coefficients of this transformation depend on the infrared colour density of the printing colour black, for which the corresponding correlations are determined empirically. The effective colour area for the printing colour black depends on the infrared colour density which is likewise determined empirically. The effective colour areas for the chromatic colours are calculated using a modified approach according to Neugebauer using the transformed standard colour values. <IMAGE>

IPC 1-7

B41F 33/00

IPC 8 full level

B41F 33/00 (2006.01)

CPC (source: EP)

B41F 33/0045 (2013.01)

Designated contracting state (EPC)

AT CH DE FR GB IT LI SE

DOCDB simple family (publication)

EP 0649743 A1 19950426; EP 0649743 B1 19970409; AT E151349 T1 19970415

DOCDB simple family (application)

EP 94115333 A 19940929; AT 94115333 T 19940929