PROCESS FOR MANUFACTURING PHOTOPOLYMER PLATES

摘要

The invention relates to a process for manufacturing photopolymer plates, in which a photopolymerizable mixture containing a thermoplastically-processible, elastomeric polymer, an ethylenically mono- or polyunsaturated compound which can be polymerized by free radicals and has a boiling point at normal pressure of over 100.degree.C, and also a compound or compound combination which is capable of initiating a polymerization of the unsaturated compounds on exposure to actinic light, is fed into a screw-type extruder, melted and degassed therein and is finally fed through a sheet die to a calender nip in which the molding to thickness takes place. The process comprises premixing the constituents of the photopolymerizable mixture before feeding them to the extruder by bringing the thermoplastic polymer, which is taken in granular form, into contact with liquid constituents of the mixture until the latter have been absorbed by the granules and then covering the granules with the dust of a powder which is insoluble in the liquids and has a particle size of 0.005 to 50 .mu.m. Optimally mixed products of uniform layer thickness are obtainable by the process.