Process for modifying surfaces using photopolymerizable elements comprising hydrophilic colloids and polymerizable monomers

Abstract

Abstract A photopolymerizable dispersion coated on a hydrophobic strippable support and comprising a continuous phase with a hydrophilic organic, macromolecular polymer dispersion medium, e.g., gelatin, and a dispersed phase including at least one addition polymerizable ethylenically unsaturated monomer, e.g., an acrylic or methacrylic acid polyester such as pentaerythritol triacrylate, and a photoinitiator is used to make diffusion resist layers suitable for modifying imagewise, surfaces by diffusion etching, plating, dyeing, alteration of sensitivity of radiation-sensitive layers, etc. On exposure to actinic radiation, the dispersed monomer droplets, having a lightactivatable initiating system in active association therewith, polymerize or harden to various degrees depending on the amount of actinic radiation received and the layer becomes resistant to diffusion of aqueous, or other normally gelatin diffusible liquids used to make solutions of materials used to modify a surface by diffusion treatment. Exposure may be through any suitable photographic stencil or pattern and this leaves an image in the resist-forming layer. The exposed resist layer may be pressed against and transferred to a moistened surface, e.g., a metal plate, and the hydrophobic support stripped off. The resist-bearing surface is then modified by diffusion of an aqueous, e.g., aqueous ferric chloride, etching solution to produce a permanently modified surface such as, in the case of using an aqueous ferric chloride etching solution applied to a copper surface, a gravure printing plate. The photopolymerizable dispersion may be coated directly on a surface to be modified and exposed through a suitable transparent photographic image, e.g., a halftone image or a gravure screen and a continuous tone image and etched and the resist removed. The photopolymerizable layer on the hydrophobic support may be laminated to the surface to be modified, and before or after removal of said support, the layer is exposed. The resist bearing surface can then be modified by diffusion etching, plating, e.g., electroplating, dyeing, alteration of the sensitivity of radiation-sensitive layers, etc.

Inventors

• 👤 J Gervay
• 👤 P Walker

Bibliographic Details