Abstract: A shallow relief non-bottoming printing plate is disclosed having a polymerized layer of less than about 0.020 inch and which includes a plurality of dispersed particles sufficient to create small protuberances in non-image or background areas to prevent bottoming. Photopolymerizable elements, as well as processing techniques, are also disclosed for making such printing plates.

Abstract: A photopolymerizable composition and photosensitive elements produced therefrom are disclosed. The photopolymerizable composition includes: (a) a monomer component, (b) a polymer component, (c) a photopolymerization initiator, and (d) an activator.The monomer component contains at least one water soluble, monofunctional unsaturated ethylenic monomer or the combination of such a monomer and at least one polyfunctional unsaturated ethylenic monomer.The polymer component includes a partially saponified water soluble, polyvinyl acetate polymer compatible with the monomer components. The polyvinyl acetate polymer contains both acetyl and hydroxyl groups and has a polymerization degree of from 300-2000. The degree of saponification of the polymer is desirably in the range of 65 to 99 percent.

Abstract: A photo-sensitive composition for dry formation of image comprising a dyestuff having a photo-fading property, a ketonic sensitizing agent and a high molecular polymer as a binding agent, which can provide a visible image by the irradiation of light and maintain the image without any fixing treatment.

Abstract: A photopolymerizable composition and photosensitive elements produced therefrom are disclosed. The photopolymerizable composition includes: (a) a monomer component, (b) a polymer component, (c) a photopolymerization initiator, and (d) an activator.The monomer component contains at least one water soluble, monofunctional unsaturated ethylenic monomer or the combination of such a monomer and at least one polyfunctional unsaturated ethylenic monomer.The polymer component includes a partially saponified water soluble, polyvinyl acetate polymer compatible with the monomer components. The polyvinyl acetate polymer contains both acetyl and hydroxyl groups and has a polymerization degree of from 300-2000. The degree of saponification of the polymer is desirably in the range of 65 to 99 percent.

Abstract: Letterpress and offset photopolymer printing plates are disclosed having relatively thin water developable photopolymer layers, which, after being developed, have ink-repulsive, non-image areas. Adhesive layers are provided in the disclosed printing plates that are interposed between an ink-repulsive coating contained in the printing plate substrate and the water-developable photopolymer, and provide a balance between satisfactory adhesive and ink-repulsive properties in the resulting plate.

Abstract: A photopolymerizable composition and photosensitive elements produced therefrom are disclosed which include a monomer component, a polymer component and a polymerization initiator activatable by actinic light. The monomer component includes at least one water soluble monofunctional unsaturated ethylenic monomer, and at least one polyfunctional unsaturated ethylenic monomer. The polymer component includes a partially saponified, water-soluble, polyvinyl acetate which is compatible with said monomer components. The ratio, by weight, of polyfunctional monomer to monofunctional monomer is in the range of about 0.2 to about 0.6, and the ratio, by weight, of said monomer component to said polymer component is in the range of about 0.7 to about 1.2.