Patent ID: 6723492
Filing Date: 2004-04-20
Classification: B41C,B41N,G03F,Y10S

Abstract:
A method for preparing a lithographic printing plate comprising exposing imagewise a lithographic printing plate precursor comprising a water-resistant support having provided thereon a light-sensitive layer with a radiation in a visible range, so that the surface of the light-sensitive layer in the exposed area is undergone polar conversion to a hydrophilic condition to form a non-image portion which accepts dampening water but repels printing ink at the time of printing while the surface of the light-sensitive layer in the unexposed area maintains the inherent hydrophobic property to form an ink-receptive image portion, wherein the light-sensitive layer contains:fine titanium oxide grains doped with a metallic ion which absorb a visible ray; and a complex comprising an organo-metallic polymer which is formed by a hydrolysis polymerization condensation reaction of a compound represented by formula (I) shown below and an organic polymer which has a group capable of forming a hydrogen bond with the organo-metallic polymer: (R0)nM(Y)xâˆ’nâ€ƒâ€ƒ(I) wherein R0 represents a hydrogen atom, a hydrocarbon group or a heterocyclic group; Y represents a reactive group; M represents a metallic atom having from 3 to 6 valences; x represents a valence of the metallic atom M; and n represents 0, 1, 2, 3, 4, 5 or 6, provided that the balance of xâˆ’n is not less than 2.