Printing plate and methods of making and use same

Claim 1

A method of printing lithographically with a planographic printing plate, which comprises: providing, in order, onto an aluminum hydrophilic printing plate substrate, a polymeric photosensitive water-insoluble hydrophilic layer comprising a hydrophilic macromolecular organic binder, a photopolymerizable ethylenically unsaturated monomer capable of promoting insolubilization or hardening in areas of photoexposure, said monomer having at least one terminal ethylenic group capable of forming a high polymer by free-radical initiated, chain-propagated addition polymerization, and a free-radical generating, addition polymerization-initiating system activatable by actinic radiation, and an overlying polymeric photosensitive hydrophobic layer comprising a hydrophobic macromolecular organic binder, a photopolymerizable ethylenically unsaturated monomer capable of promoting insolubilization or hardening in areas of photoexposure, said monomer having at least one terminal ethylenic group capable of forming a high polymer by free-radical initiated, chain propagated addition polymerization, and a free-radical generating, addition polymerization-initiating system activatable by actinic radiation; photoexposing simultaneously areas of each of said layers of said plate, sufficiently to photoinsolubilize or photoharden each of said layers in said areas; placing said photoexposed plate, without further processing, onto a printing press, said printing press being adapted to receipt of a printing plate and being provided with an oleophilic ink and a fountain solution for contact with said plate during operation of said printing press; and operating said printing press, thereby to contact said photoexposed plate with said ink and said fountain solution during said operation and to remove with said fountain solution non-exposed areas of said hydrophobic layer for the baring of corresponding areas of said water-insoluble hydrophilic layer.

Claim 2

A method of printing lithographically with a planographic printing plate, which comprises: providing, in order, onto an aluminum hydrophilic printing plate substrate, a polymeric photosensitive water-insoluble hydrophilic layer comprising a hydrophilic macromolecular organic binder, a photopolymerizable ethylenically unsaturated monomer capable of promoting insolubilization or hardening in areas of photoexposure, said monomer having at least one terminal ethylenic group capable of forming a high polymer by free-radical initiated, chain-propagated addition polymerization, and a free-radical generating, addition polymerization-initiating system activatable by actinic radiation, and an overlying polymeric photosensitive hydrophobic layer comprising a hydrophobic macromolecular organic binder, a photopolymerizable ethylenically unsaturated monomer capable of promoting insolubilization or hardening in areas of photoexposure, said monomer having at least one terminal ethylenic group capable of forming a high polymer by free-radical initiated, chain propagated addition polymerization, and a free-radical generating, addition polymerization-initiating system activatable by actinic radiation; photoexposing simultaneously areas of each of said layers of said plate, sufficiently to photoinsolubilize or photoharden each of said layers in said areas; placing said photoexposed plate, without further processing, onto a printing press, said printing press being adapted to receipt of a printing plate and being provided with an oleophilic ink and a fountain solution for contact with said plate during operation of said printing press; and operating said printing press, thereby to contact said photoexposed plate with said ink and said fountain solution during said operation and to remove with said fountain solution non-exposed areas of said hydrophobic layer for the baring of corresponding areas of said water-insoluble hydrophilic layer.