METHOD FOR MAKING A LITHOGRAPHIC PRINTING PLATE

摘要

A method for making a lithographic printing plate is disclosed which comprises the steps of: (1) providing a heat-sensitive lithographic printing plate precursor comprising on a support having a hydrophilic surface or which is provided with a hydrophilic layer, a heat-sensitive coating, (2) image-wise exposing said precursor with IR-radiation or heat, and (3) developing said image-wise exposed precursor with an alkaline developing solution, characterised in that an antisludge agent is present in said precursor or in said developing solution or in said precursor and said developing solution, and wherein said antisludge agent is a 5-membered heteroaromatic compound, comprising a -NH-group wherein said hydrogen is capable of being deprotonated in said alkaline developing solution, selected from the group consisting of an optionally substituted benztriazole, 1, 2 , 3-triazole, tetrazole or indazole compound. According to the above method, the formation of sludge is inhibited or reduced.