PROCESSLESS DIRECT WRITE IMAGING MEMBER CONTAINING POLYMER GRAFTED CARBON AND METHODS OF IMAGING AND PRINTING

摘要

An imaging member, such as a negative-working printing plate or on-press cylinder, can be prepared with a hydrophilic imaging layer comprised of a heat-sensitive hydrophilic polymer having ionic moieties and a polymer grafted carbon as a photothermal conversion material. The heat-sensitive polymer and polymer grafted carbon can be formulated in water or water-miscible solvents without agglomeration. In the imaging member, the polymer reacts to provide increased hydrophobicity in areas exposed to energy that provides or generates heat. For example, heat can be supplied by laser irradiation in the IR region of the electromagnetic spectrum. The heat-sensitive polymer is considered 'switchable' in response to heat, and provides a lithographic image without wet processing.