摘要 |
A method is disclosed wherein a positive-working heat-sensitive lithographic printing plate precursor is prepared comprising the steps of: (i) providing a support having a hydrophilic surface or which is provided with a hydrophilic layer, (ii) coating a first solution comprising a first polymer, said first polymer being soluble in an alkaline solution, (iii) coating a second solution comprising a heat-sensitive positive-working imaging composition, and (iv) coating a third solution comprising a third polymer or surfactant wherein said third polymer or said surfactant reduce the penetrability of an alkaline developer solution into the coating. The printing plates obtained by this method exhibits a reduced dot-loss, resulting in an improved developing latitude.
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