Abstract: A directly imageable raw plate for waterless planographic printing plate, in which a heat insulating layer, heat sensitive layer and ink repellent layer are formed in this order on a substrate, comprising physical properties of 5 to 100 kgf/mm.sup.2 in initial elastic modulus and 0.05 to 5 kgf/mm.sup.2 in 5% stress as tensile properties of the heat sensitive layer or the heat insulating layer or the laminate consisting of both the layers.It can be suitably used also for large printing presses and web offset printing presses requiring high printing durability, and makes it possible to obtain an economically advantageous printing plate.

Abstract: The present invention is a water-less lithographic printing plate, in which a photosensitive layer and a silicone rubber layer are laminated in this order on a substrate, characterized in that the photosensitive layer contains the reaction product between a compound with at least one each of phenolic hydroxyl groups and non-phenolic hydroxyl groups and a quinonediazide compound, or contains both the reaction product between a compound with at least one of phenolic hydroxyl groups and a quinonediazide compound, and the reaction product between a compound with at least one of non-phenolic hydroxyl groups and a quinonediazide compound.The water-less lithographic raw plate of the present invention is excellent in image reproducibility and printing durability, and so can be favorably and economically advantageously used also in the commercial web offset printing and the newspaper web offset printing where high printing durability is required.

Abstract: The present invention is concerned with a photosensitive polymer composition for a water-developable, flexographic printing plate, having a phase separating structure in a sea-and-islands state, the phase separating structure comprising island phases and a sea phase, the island phase comprising a thermoplastic elastomer component having a glass transition temperature lower than 25.degree. C., and the sea phase comprising a gelled, ethylenically unsaturated compound component.The photosensitive polymer composition of the present invention affords a printing plate capable of being developed with neutral water and suitable for flexographic printing using a water-based ink.