A coating solution useful in the preparation of printing plate precursors comprises: a) a radiation sensitive composition C comprising a phenolic resin; b) at least one thermoplastic polymer P which has a solubility in aqueous alkaline media ranging from sparingly soluble to insoluble; c) a first solvent component A which is capable of solubilizing both composition C and thermoplastic polymer P; d) a second solvent component B having a volatility less than component A, wherein component B is capable of volatilizing composition C but not thermoplastic polymer P, and composition C and thermoplastic P are homogeneously dissolved in a mixture of components A and B; and e) at least one further polymer AP having a higher molecular weight than the phenolic resin of composition C, wherein polymer AB is miscible with the phenolic resin and immiscible with thermoplastic polymer P. The coating provides a radiation-sensitive layer for the substrate, and the coating contains homogeneously distributed thermoplastic polymer particles.