US 5,206,102 A · Photoelectrochemical imaging system

Abstract

A method and apparatus are provided for photoelectrochemical reproduction of an image on a plate or roller. For a printing press, the apparatus includes a reusable image roller coated with a oxide semiconductor. A plating solution is applied to the image roller as a thin film. The desired image is written onto the oxide semiconductor by a laser that generates a photoelectrochemical reaction between the semiconductor and the plating solution. In a preferred embodiment, the image roller is coated with hydrophilic p-type NiO. The image is written onto the roller as dots of oleophilic metallic copper, which are formed on the NiO coating by laser-generated cathodic photoelectrodeposition. Subsequent erasure of the metallic copper image can be accomplished by chemical or electrochemical dissolution of the deposited copper. The method functions to create, erase, and recreate high-resolution images directly on a printing press roller without the necessity of precise matrix registration.

Claims15

Dependent claims

A method of reproducing an image on a printing plate, comprising the steps of:

providing a surface layer of hydrophilic semiconductor material on the plate;
applying a film of a metal plating solution on said surface layer of semiconductor material;
illuminating selected areas of said surface layer of semiconductor material through said film of plating solution;
and
photoelectrochemically depositing a layer of oleophilic metal plating material on said illuminated areas of said surface layer of semiconductor material to form the image.

2 more elements

Dependencies are inferred from the claim text.

Photoelectrochemical imaging system

Life of this patent

Photoelectrochemical imaging system

Life of this patent

Abstract

Claims15