Deleting fluid for printing plates and method for deletion

摘要

This invention provides a method for deleting images formed on offset printing plates which comprises treating the surface of undesired portion of the images formed by exposure and development with a deletion fluid which contains a ferric complex salt of an organic acid and 0.3 mol/liter or more of at least one compound selected from the group consisting of a soluble bromide and a soluble iodide. Preferred ferric complex salt is a ferric complex salt of aminopolycarboxylic acid.