Method for erasing a lithographic printing master

摘要

A method is disclosed for removing ink accepting areas of a printing surface of a lithographic printing master by treatment with an atmospheric plasma. Preferably, the plasma is directed to the printing surface as a plasma jet while the printing master is mounted on the plate cylinder of a printing press. The method enables to clean a support of a printing master and then reuse the cleaned support for making another printing master. Preferably, all the following steps are performed on-press:(i) making an imaging material by providing a support with an image recording layer; (ii) making a printing master having a printing surface comprising ink accepting areas by image-wise exposing and optionally developing the imaging material; (iii) starting a pressrun; (iv) a cleaning step using an atmospheric plasma and then repeating steps (i) to (iv).