PROCESS FOR THE MANUFACTURE OF PLANOGRAPHIC PRINTING FORMS

摘要

This invention relates to an improvement in the process for the manufacture of a planographic printing form in which a light-sensitive material comprising a support having a hydrophilic surface and a copying layer thereon containing a light-sensitive diazo or azido compound is imagewise exposed, developed, and then beated sufficiently long and at such a temperature, at least 180.degree.C, that the oleophilic image areas are decomposed and a deposit is formed in the hydrophilic background areas, the improvement comprising, after development but prior to the thermal treatment, treating the entire surface of the plate with an aqueous solution of at least one member selected from the group consisting of a water-soluble organic substance and a water-soluble inorganic salt.