Method for Processing a Lithographic Printing Plate

A method for processing a heat-sensitive positive-working lithographic printing plate material which comprises on a support having a hydrophilic surface or which is provided with a hydrophilic layer, a heat and/or light-sensitive coating which comprises at least two layers:

• a first layer comprising an oleophilic resin and/or a vinyl acetal (co)polymer and
• a second layer comprising a (co)polymer which is located between the support and the first layer;
• the method comprising:
• treating the plate material with an alkaline development solution,
• treating the plate material with a first gum solution and consecutively with a second gum solution which are configured as a cascade whereby the second gum solution overflows into the first gum solution and which gum solutions include a buffer;
• characterized in that the pH of the first gum solution reaches a steady state value above the pKa value of the (co)polymer present in the second layer.