Method for the preparation of a negative working printing plate

摘要

A method for the preparation of a negative working lithographic printing plate by means of ink jet printing is disclosed. This method uses a lithographic printing plate precursor comprising a lithographic support and an image forming layer containing a polymeric binder soluble in an aqueous alkaline developer. The precursor is image-wise printed by an ink jet fluid comprising a compound capable of reducing the solubility of said binder in said aqueous alkaline developer. After development a negative working printing plate is obtained.