Radiation sensitive lithographic printing plate precursors having ablation-free imageable composition and method

A process for producing a negative-working lithographic printing plate comprising in order:

• (a) applying to a substrate an oleophilic base layer comprising an oleophilic polymer containing functional reactive groups, and a photothermal converter;
• (b) applying over said oleophilic base layer a hydrophilic top layer to form a layered composition, said top layer comprising a crosslinkable hydrophilic polymer capable of interlayer chemical bonding with the reactive groups of said oleophilic polymer in the base layer;
• (c) overall exposing said layered composition to energy sufficient to crosslink said hydrophilic polymer and to interlayer chemically bond said hydrophilic polymer with the functional reactive groups of the oleophilic polymer in the base layer to provide an interlayer adhesive bond between said top layer and said base layer;
• (d) imagewise exposing said printing plate precursor to laser radiation to produce exposed and unexposed areas, whereby said interlayer adhesive bond is non-ablatively selectively weakened in radiation-exposed areas to provide an imaged printing plate precursor;
• (e) mounting said imaged printing plate precursor on a lithographic printing press;
• and
• (f) contacting said plate precursor with fountain solution and ink so that said hydrophilic top layer is removed in said imagewise exposed areas to reveal the oleophilic base layer, while retaining the interlayer adhesive bond between the base layer and the hydrophilic top layer in said unexposed areas.