Abstract: According to the present invention there is provided a method for the preparation of a lithographic printing plate comprising the steps of exposing with IR light an imaging element comprising on a lithographic base with a hydrophilic surface a first layer including a polymer, soluble in an aqueous alkaline solution and a top layer on the same side of the lithographic base as the first layer which top layer is IR-sensitive and unpenetratable for or insoluble in an alkaline developer wherein said first layer and said top layer may be one and the same layer, said imaging element comprising a siloxane surfactant; developing said exposed imaging element with an alkaline solution; rinsing said developed imaging element with water or an aqueous solution; gumming said developed imaging element with a baking gum solution; subjecting said gummed imaging element to a thermal treatment at a temperature above 50° C.