Chromogenic process for the production of color images using a color photographic recording material, which contains embedded color developer compounds that can be activated by heat treatment

US6013420A · kind A · utility

Assignee

• Agfa-Gevaert NV · BE

Inventors

• Kaspar Wingender · Leverkusen, DE
• Gunther Schenk · Cologne, DE

Key dates

• Filing date: Jun 5, 1998
• Grant date: Jan 11, 2000
• Expiry date: Jun 5, 2018

Classification

• Technology area (CPC G): Physics
• CPC primary: G03C8/402
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A chromogenic process for the production of color images using, a color photographic recording material with at least one light-sensitive silver halide emulsion layer to which are assigned a thermosolvent, a color coupler and a color developer compound, and optionally further non light-sensitive layers, by exposure and development in an aqueous alkaline treatment bath (activator bath), characterised by the following features (a) and (b): PA1 (a) the color developer compound is assigned to the silver halide emulsion layer in the form of an inactive precursor compound corresponding to formula I (capped color developer compound): ##STR1## wherein: R.sup.1 and R.sup.2 (the same or different) mean alkyl with up to 6 carbon atoms; PA2 R.sup.3, R.sup.4, R.sup.5 and R.sup.6 (independently of one another) mean H, halogen, --OH, alkyl, alkoxy, acylamino or sulphonamido; PA2 M.sup.+ means an alkali metal ion, NH.sub.4.sup.+, a cation derived from a nitrogen-containing organic base, or a compound with a quaternary ammonium group, PA1 (b) the recording material undergoes a heat treatment prior to development in order to convert the capped color developer compound to an active form capable of co…