Process for producing support for lithographic printing plate

摘要

A process for producing a support for a lithographic printing plate is described, which comprises jetting a high-pressure liquid from at least one nozzle at a high rate, joining the jetted stream with a slurry containing a fine abrasive powder having a specific gravity of not less than 2.5 and having a sharp-angled tip having a radius of not more than 20 mu m, said slurry being spouted from at least one spout, directing the resulting mixed stream to strike against a surface of a metal sheet to carry out first graining, and modifying the first roughness thus formed on the metal sheet by brush graining to form a second roughness. Lithographic printing plates produced by using the resulting support are free from stain formation during printing and exhibit satisfactory printing durability.