Radiation-sensitive mixture and recording material made thereof for offset printing plates

US6100004A · kind A · utility

Assignee

• Agfa-Gevaert NV · BE

Inventors

• Andreas Elsaesser · Idstein, DE
• Otfried Gaschler · Wiesbaden, DE
• Helmut Haberhauer · Taunusstein, DE
• Mathias Eichhorn · Niedernhausen, DE
• Fritz-Feo Grabley · Königstein, DE
• Thomas Leichsenring · Mainz, DE
• Gabor I. Koletar · Berkeley Heights, US
• Douglas A. Seeley · High Bridge, US

Key dates

• Filing date: Mar 11, 1998
• Grant date: Aug 8, 2000
• Expiry date: Mar 11, 2018

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B41C2210/262
• WIPO field: Textile and paper machines
• WIPO sector: Mechanical engineering

Abstract

A positive-working or negative-working radiation-sensitive mixture includes as an IR absorbing component a carbon black pigment having a primary particle size smaller than 80 nm. The carbon black pigment is predispersed in a polymer containing acidic units having a pK.sub.a of less than 13. The radiation-sensitive component may include an ester of (i) a 1,2-naphthoquinone-2-diazide-4-sulfonic acid or a 1,2-naphthoquinone-2-diazide-5-sulfonic acid and (ii) a compound having at least one phenolic hydroxyl group, such as 3 to 6 phenolic hydroxyl groups. After imagewise radiation exposure, the recording material including the radiation-sensitive mixture can be developed without difficulties in an aqueous alkaline solution without leaving residual coating on the areas that became soluble or that remained soluble upon exposure.