Thermal lithographic printing plates

US6060217A · kind A · utility

Assignee

• Kodak Polychrome Graphics Company Ltd. · US

Inventors

• My T. Nguyen · Duyen Hai Town, VN
• Nishith Merchant · Union City, US
• Ken-ichi Shimazu · Briarcliff Manor, US
• S. Peter Pappas · Juno Beach, US
• Robert W. Hallman · San Diego, US
• Jerome Kesselman · Yorktown Heights, US
• Celin Savariar-Hauck · Badenhausen, DE
• Gerhard Hauck · Badenhausen, DE
• Hans-Joachim Timpe · Biberach an der Riß, DE
• Omkar J. Natu · Hackettstown, US
• Ajay Shah · Livingston, US

Key dates

• Filing date: Sep 2, 1997
• Grant date: May 9, 2000
• Expiry date: Sep 2, 2017

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S430/145
• WIPO field: Textile and paper machines
• WIPO sector: Mechanical engineering

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. Within a short t…