Inventors:
My T. Nguyen - Cliffwood NJ
Nishith Merchant - North Bergen NJ
Ken-Ichi Shimazu - Briaicliff Manor NY
S. Peter Pappas - Wood Ridge NJ
Robert Hallman - Palinskle Park NJ
Jerome Philip Kesselman - Yorktown Heights NY
Celin Savariar-Hauck - Badenhausen, DE
Gerhard Hauck - Badenahusen, DE
Hans-Joachim Timpe - Osterode, DE
Omkar J. Natu - Warren NJ
Ajay Shah - Livingston NJ
Assignee:
Kodak Polychrome Graphics LLC - Norwalk CT
International Classification:
G03F 730
Abstract:
A method for directly imaging a lithographic printing surface using infrared radiation without the requirement of pre- or post-UV-light exposure, or heat treatment employs a printing plate which contains a support with a hydrophilic surface overcoated with an imaging layer. The imaging layer contains at least one polymer having bonded pendent groups which are hydroxy, carboxylic acid, tert-butyl-oxycarbonyl, sulfonamide, amide, nitrile, urea, or combinations thereof; as well as an infrared absorbing compound. The imaging layer may contain a second polymer which has bonded pendent groups which are 1,2-napthoquinone diazide, hydroxy, carboxylic acid, sulfonamide, hydroxymethyl amide, alkoxymethyl amide, nitrile, maleimide, urea, or combinations thereof. The imaging layer may also contain a visible absorption dye, a solubility inhibiting agent, or both. In practice, the imaging layer is imagewise exposed to infrared radiation to produce exposed image areas in the imaged layer which have transient solubility in aqueous alkaline developing solution, so that solubility is gradually lost over a period of time until the imaged areas become as insoluble as non-imaged areas.
