Method for producing a plate or sheet useful in planographic printing

摘要

A method for producing a plate or sheet useful in planographic printing which comprises providing a substrate of an oleophilic resin having in the molecules thereof carbon-carbon double bonds and/or carbon atoms bonded with a single hydrogen atom in a total amount of not less than 0.05 mol/kg, contacting the substrate with a hydrophilic radical polymerizable compound and exposing the substrate contacted with the compound to actinic way to form a plate having a hydrophilic thin layer chemically combined with the substrate. The substrate may be mixed with conductive or semiconductive powder uniformly dispersed in the oleophilic resin so as to have a volume resistivity in the range of from 10-3 to 108 ohm.cm. In doing so, an electrical printing plate making method which is very advantageous in easiness and usefulness is applicable to the plate or sheet for planographic printing according to the invention.