NEGATIVE-WORKING LITHOGRAPHIC PRINTING PLATE PRECURSORS

摘要

A lithographic printing plate precursor comprises an imageable layer comprising a free radically polymerizable component, an initiator composition capable of generating free radicals upon exposure to imaging infrared radiation, an infrared radiation absorbing dye comprising an infrared radiation absorbing cation and a counter anion, and a polymeric binder. The salt formed between the infrared radiation absorbing cation and a tetraphenyl borate has solubility in 2-methoxy propanol at 20°C that is greater than or equal to 3.5 g/1. The use of these infrared radiation absorbing dyes in the imageable layers provides a reduced tendency of these dyes to crystallize in the presence of tetraaryl borate counter anions.