Patent ID: 7425405

Claim:
A method for making a lithographic printing plate comprising the steps of: (i) providing a heat-sensitive, negative-working printing plate precursor which is not sensitive to visible and UV light comprising a support with a hydrophilic surface or which comprises a hydrophilic layer and a coating provided thereon, the coating comprising an image-recording layer which comprises hydrophobic thermoplastic polymer particles and a hydrophilic binder, wherein the hydrophobic thermoplastic polymer particles have an average particle size in the range from 45 nm to 55 nm, and wherein the amount of the hydrophobic thermoplastic polymer particles in the image-recording layer is between 75% and 85% by weight relative to the weight of the image-recording layer; (ii) exposing the coating to heat or infrared light sufficient to induce coalescence of the thermoplastic polymer particles at exposed areas of the coating; and (iii) developing the precursor by applying an aqueous alkaline solution, thereby removing non-exposed areas of the coating from the support, wherein the aqueous alkaline solution has a pH ≧10 and comprises a surfactant.