Photographic compositions and elements spectrally sensitized with new methine dyes
AssigneeEastman Kodak Company
InventorYasushi S. Yamamoto
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Abstract
Photographic silver halide compositions and elements are provided which are spectrally sensitized with new methine dyes. The dyes are prepared from new intermediate compounds which have an acetylenically unsaturated hydrocarbon chain terminated with a nucleophilic group, the acetylenically unsaturated hydrocarbon chain being bonded to a nitrogen atom in a heterocyclic ring system of the type used in cyanine dyes. The new intermediates also provide alternative synthetic routes to known dyes.
Claims9
In a radiation-sensitive silver halide composition, the improvement wherein said composition is spectrally sensitized by means of a methine dye comprising first and second nuclei joined by a methine linkage, at least said first nucleus comprising a heterocyclic nitrogen ring or ring system having attached to a nitrogen atom thereof, an acetylenically unsaturated hydrocarbon chain terminated by a nucleophilic group.
A radiation-sensitive silver halide composition spectrally sensitized by means of a dye selected from the group consisting of:
- a. anhydro 5,6-dichloro-1,3'-diethyl-3-(4-sulfo-2-butyn-1-yl) benzimidazolothiacarbocyanine hydroxide;
- b. anhydro 5,6-dichloro-1,3'-diethyl-3-(4-thiosulfato-2-butyn-1-yl) benzimidazolothiacarbocyanine hydroxide;
- and
- c. anhydro 5,6-dichloro-1,3'-diethyl-3-(4-sulfo-2-butyn-1-yl) benzimidazolooxacarbocyanine hydroxide.
A radiation-sensitive composition comprising silver halide and a spectrally sensitizing quantity of a methine dye comprising first and second nuclei joined by a methine linkage, at least said first nucleus comprising a heterocyclic nitrogen ring or ring system having attached to a nitrogen atom thereof, an acetylenically unsaturated hydrocarbon chain terminated by a nucleophilic group.
Dependencies are inferred from the claim text.