Fragmentable electron donor compounds combined with broad blue spectral sensitization

US6509144B1 · kind B1 · utility

Assignee

• EASTMAN KODAK COMPANY · US

Inventors

• Kenneth J. Reed · Brighton, US
• Joseph P. Pepe · Rochester, US
• James A. Friday · Rochester, US
• Jon N. Eikenberry · Rochester, US
• Yun Chang · Rochester, US
• Annabel A. Muenter · Rochester, US
• Jerome R. Lenhard · Fairport, US

Key dates

• Filing date: Jan 25, 1999
• Grant date: Jan 21, 2003
• Expiry date: Jan 25, 2019

Classification

• Technology area (CPC G): Physics
• CPC primary: G03C1/28
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

This invention comprises a photographic element comprising a support and at least one blue sensitive silver halide emulsion layer containing a tabular grain silver halide emulsion, or an emulsion in which the halide content is at least 50% chloride and no more than 5% iodide, wherein the emulsion is spectrally sensitized with at least one dye providing a peak sensitization between 446 and 500 nm and at least one dye providing a peak sensitization between 400 and 445 nm and additionally sensitized with a fragmentable electron donor of the formula: X—Y′. or an electron donor which contains an —XY′ moiety;whereinX is an electron donor moiety, Y′ is a leaving proton H or a leaving group Y, with the proviso that if Y′ is H a base, &bgr;−, is covalently linked directly or indirectly to X. and wherein:1) X—Y′ has an oxidation potential between 0 and about 1.4 V; and2) the oxidized form of X—Y′ fragments to give the radical X• and the leaving fragment Y′; and, optionally,3) the radical X• has an oxidation potential ≦−0.7V (that is, equal to or more negative than about −0.7 V).