Reducing post-process D.sub.min increase in positive redox dye-releasing image transfer systems using oxidants in cover sheets

US4409315A · kind A · utility

Assignee

• EASTMAN KODAK COMPANY · US

Inventors

• Eugene A. Armour · Rochester, US
• Richard P. Henzel · Webster, US
• Rowland G. Mowrey · Rochester, US

Key dates

• Filing date: Jun 28, 1982
• Grant date: Oct 11, 1983
• Expiry date: Jun 28, 2002

Classification

• Technology area (CPC G): Physics
• CPC primary: G03C11/08
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

Photographic assemblages are described employing positive-working redox dye-releasers and a cover sheet containing an oxidant having an electrode potential of from about -200 mV up to about 1000 mV versus a saturated calomel electrode at a pH of about 5 to about 6. The oxidant is capable of oxidizing electron transfer agent in the system. The reduced form of the oxidant is incapable of reducing the positive-working redox dye-releaser. After processing, the oxidant reacts with the electron transfer agent to prevent it from reacting with the dye releaser which would otherwise cause further dye release. D.sub.min stability is thereby improved.