Method for the preparation of a planographic printing plate using NiS containing nuclei

US4563410A · kind A · utility

Assignee

• Agfa-Gevaert NV · BE

Inventors

• Antoine A. De Jaeger · Wilrijk, BE
• Alfons Bertels · Diepholz, DE
• Albert Lucien Poot · Kontich, BE
• Rene De Keyzer · Bornem, BE
• Francis J. Sels · Kontich, BE

Key dates

• Filing date: Aug 15, 1984
• Grant date: Jan 7, 1986
• Expiry date: Aug 15, 2004

Classification

• Technology area (CPC G): Physics
• CPC primary: G03F7/07
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A method for the preparation of a planographic printing plate wherein a sheet material, which comprises an exterior hydrophilic colloid layer having concentrated on its surface a silver image formed by the silver complex diffusion transfer process with NiS or mixed crystal NiS.Ag.sub.2 S development nuclei in which the molar ratio of NiS to Ag.sub.2 S is not smaller than 1:1, is treated with a liquid for hydrophobizing the silver image for planographic printing, such liquid containing in dissolved state a heterocyclic compound corresponding to one of the following tautomeric structures (A) and (B) or (C) and (D): ##STR1## wherein: R.sup.1 represents hydrogen, amino or acylamino, PA0 R.sup.2 represents an alkyl group, and PA0 R.sup.3 represents an alkyl group, or an alkanamido-arylene group.