Global Patent Index - EP 1614541 A2

EP 1614541 A2 20060111 - Method of making a lithographic printing plate.

Title (en)

Method of making a lithographic printing plate.

Title (de)

Verfahren zur Herstellung einer lithographischen Druckplatte

Title (fr)

Procédé pour la fabrication d'une plaque d'impression lithographique

Publication

EP 1614541 A2 20060111 (EN)

Application

EP 05106259 A 20050708

Priority

  • EP 04103252 A 20040708
  • EP 05105440 A 20050621
  • EP 05106259 A 20050708

Abstract (en)

A method for making a lithographic printing plate is disclosed which comprises the steps of : i) providing a lithographic printing plate precursor comprising an aluminum support with a grained and anodized surface having CIE 1976 color coordinates L* sup which is not less than 70 and a* sup and b* sup each in the range from -4 to +4; and a coating on said support which comprises an image-recording layer comprising an infrared-sensitized photopolymerizable or photocurable composition; which together form a coated support having a CIE 1976 lightness value L* nonexp which is not less than 50; ii) image-wise exposing the coating to infrared light, thereby inducing polymerization or curing of the composition at exposed areas; and forming a visible print-out image in the coating of which the lightness difference ”L* is at least 5, wherein ”L* is defined as L* nonexp minus L* exp , wherein L* exp is the CIE 1976 lightness value of the coated support at exposed areas; iii) removing non-exposed areas of the coating with a developer. The combination of an essentially white support, an essentially colorless or only slightly colored coating and a lightness difference between non-exposed and exposed areas of at least 5 provides a print-out image with a high contrast, which enables convenient image quality control before developing the plate.

IPC 8 full level

B41C 1/10 (2006.01)

CPC (source: EP)

B41C 1/1008 (2013.01); B41C 2210/04 (2013.01); B41C 2210/06 (2013.01); B41C 2210/22 (2013.01); B41C 2210/24 (2013.01); B41C 2210/26 (2013.01)

Citation (applicant)

Designated contracting state (EPC)

AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU LV MC NL PL PT RO SE SI SK TR

DOCDB simple family (publication)

EP 1614541 A2 20060111; EP 1614541 A3 20060607

DOCDB simple family (application)

EP 05106259 A 20050708