Abstract: Photothermographic materials comprise heat-bleachable antihalation compositions in backside antihalation layers. These compositions comprise a hexaarybiimidazole and an oxonol dye that can be represented by the following Structure I: A1═L1—(L2═L3)p—(L4═L5)q—(L6═L7)r—A2−(M)k wherein A1 and A2 are the same or different activated methylene moieties, L1 through L7 independently represent a substituted or unsubstituted methine group, M represents a counterion, k is the number of M counterions necessary to provide neutral charge for Structure I, p, and q, are independently 0 or 1, and r is 0, 1, or 2. The antihalation composition is typically bleached when subjected to a temperature of at least 90° C. for at least 0.5 seconds.

Abstract: This invention provides a photographic element comprising at least one silver halide emulsion layer in which the silver halide is sensitized with a compound of the formula (a): &Dgr;−(t)m−XY′  (a) XY′−(t)m−&Dgr;  (b) &Dgr;−(t)m−XY′−(t)m−&Dgr;  (c) wherein &Dgr; is protective group that is eliminated during development of the photographic element, t is a timing group, m is an integer from 0 to 3, and XY′ is a fragmentable electron donor moiety in which X is an electron donor group and Y′ is a leaving proton H or a leaving group Y, with the proviso that if Y′ is a proton, a base, &bgr;−, is present in the emulsion or is covalently linked directly or indirectly to X, and wherein: 1) X—Y′ has an oxidation potential between 0 and about 1.

Abstract: A UV or visible-light sensitive photobleachable dye composition substantially free of polymerizable monomer comprising a photobleachable dye and an N-oxyazinium compound, a photographic element containing such a photobleachable composition, and a method for bleaching a photographic element.

Abstract: A photographic element comprising at least one silver halide emulsion layer in which the silver halide is sensitized with a compound of the formula: wherein A is a silver halide adsorptive group that contains at least one atom of N, S, Se, or Te that promotes adsorption to silver halide, and Z is a light absorbing group including for example cyanine dyes, complex cyanine dyes, merocyanine dyes, complex merocyanine dyes, homopolar cyanine dyes, styryl dyes, oxonol dyes, hemioxonol dyes, and hemicyanine dyes, and XY is an fragmentable electron donor moiety in which X is an electron donor group and Y is a leaving group other than hydrogen, and wherein: 1) XY has an oxidation potential between 0 and about 1.4 V; and 2) the oxidized form of XY undergoes a bond cleavage reaction to give the radical X• and the leaving fragment Y. In a preferred embodiment of the invention, the radical X• has an oxidation potential ≦−0.7 V.

Abstract: This invention comprises a photographic element comprising a support and at least one silver halide emulsion layer in which the silver halide is sensitized with a compound of the formula:Q-XYwherein Q represents the atoms necessary to form a chromophore comprising an amidinium-ion, a carboxyl-ion or dipolar-amidic chromophoric system when conjugated with XY, and XY is a fragmentable electron donor moiety in which X is an electron donor group and Y is a leaving group other than hydrogen, and wherein:1) XY has an oxidation potential between 0 and about 1.4 V;2) the oxidized form of XY undergoes a bond cleavage reaction to give the radical X.sup..cndot. and the leaving fragment Y.In a preferred embodiment of the invention, the radical X.cndot. has an oxidation potential <-0.7V.

Abstract: A photographic element comprising at least one silver halide emulsion layer in which the silver halide is sensitized with a compound of the formula: ##STR1## wherein A is a silver halide adsorptive group that contains at least one atom of N, S, Se, or Te that promotes adsorption to silver halide, and Z is a light absorbing group including for example cyanine dyes, complex cyanine dyes, merocyanine dyes, complex merocyanine dyes, homopolar cyanine dyes, styryl dyes, oxonol dyes, hemioxonol dyes, and hemicyanine dyes, and XY is an fragmentable electron donor moiety in which X is an electron donor group and Y is a leaving group other than hydrogen, and wherein:1) XY has an oxidation potential between 0 and about 1.4 V; and2) the oxidized form of XY undergoes a bond cleavage reaction to give the radical X.sup..cndot. and the leaving fragment Y.In a preferred embodiment of the invention, the radical X.sup..cndot. has an oxidation potential .ltoreq.-0.7 V.

Abstract: A photographic element comprises at least one silver halide emulsion layer in which the silver halide is sensitized with a compound of formulaZ-(L-XY).sub.kwherein:Z is a light absorbing group;L is a linking group containing a least one C, N, S, or O atom; andk is 1 or 2; andXY represents a fragmentable electron donor moiety wherein:1) XY has a an oxidation potential between 0 and about 1.4 V;2) X is an electron donor group;3) Y is a leaving group other than hydrogen; and4) the oxidized form of XY undergoes a bond cleavage reaction to give the radical X.sup..cndot. and the leaving fragment Y.In a preferred embodiment the radical X.sup..cndot. has an oxidation potential of .ltoreq.-0.7 V.

Abstract: This invention comprises a photographic element comprising at least one silver halide emulsion layer in which the silver halide is sensitized with a compound of the formula X--H, wherein X is an electron donor moiety to which a base, B.sup.-, is covalently linked and H is a leaving hydrogen atom, and wherein:1) X--H has an oxidation potential between 0 and about 1.4 V; and2) the oxidized form of X--H undergoes deprotonation reaction with the base B.sup.-, to give the radical X.sup..cndot. and the protonated base B-H.In a preferred embodiment of the invention, the radical X.cndot. has an oxidation potential <-0.7V.

Abstract: A photographic element comprising at least one silver halide emulsion layer in which the silver halide is sensitized with a compound of the formula: ##STR1## wherein A is a silver halide adsorptive group that contains at least one atom of N, S, Se, or Te that promotes adsorption to silver halide, and L represents a linking group containing at least one C, N, S or O atom, k is 1 or 2, and XY is an fragmentable electron donor moiety in which X is an electron donor group and Y is a leaving group other than hydrogen, and wherein:1) XY has an oxidation potential between 0 and about 1-4 V; and2) the oxidized form of XY undergoes a bond cleavage reaction to give the radical X.sup..cndot. and the leaving fragment Y.In a preferred embodiment of the invention, the radical X.sup..cndot. has an oxidation potential .ltoreq.-0.7V.

Abstract: A photographic element comprises a support and at least one silver halide emulsion layer in which the silver halide is sensitized with a fragmentable electron donor of the formula X--Y, wherein X is an electron donor moiety and Y is a leaving group other than hydrogen, and wherein:1) X--Y has an oxidation potential between 0 and about 1.4 V; and2) the oxidized form of X--Y undergoes a bond cleavage reaction to give the radical X.sup..cndot. and the leaving fragment Y.In a preferred embodiment of the invention, the radical X.sup..cndot. has an oxidation potential .ltoreq.-0.7V.

Abstract: Substituted hydroxylamine antioxidants can be prepared by reacting hydroxylamine or a mono-substituted hydroxylamine with an epoxide. The antioxidant reaction product is not removed from the reaction mixture, but is used without separation after combination with a color developer to provide a photographic color developer composition. The antioxidants are highly water soluble and thus exhibit no objectionable odor.

Abstract: Substituted hydroxylamine antioxidants can be prepared by reacting hydroxylamine or a mono-substituted hydroxylamine with an epoxide. The antioxidant reaction product is not removed from the reaction mixture, but is used without separation after combination with a color developer to provide a photographic color developer composition. The antioxidants are highly water soluble and thus exhibit no objectionable odor.

Abstract: An improved photographic developing solution is free of dihydroxybenzene developing agents such as hydroquinone, has a pH in the range of from 9.5 to 11.5 and comprises (1) an ascorbic acid developing agent, (2) an auxiliary super-additive developing agent and (3) a carbonate buffering agent in a concentration of at least 0.5 molar. The developing solution is broadly useful in black-and-white development but is most advantageously employed in a process for forming a high-contrast image utilizing a silver halide photographic element comprising a hydrazine compound which functions as a nucleating agent and an amino compound which functions as an incorporated booster. The developing solution is ecologically advantageous, exhibits excellent stability with respect to seasoning effects, and provides high speed and good upper scale contrast combined with a low level of pepper fog and a moderate degree of chemical spread.

Abstract: An improved photographic developing solution is free of dihydroxybenzene developing agents such as hydroquinone, has a pH in the range of from 9.5 to 11.5 and comprises (1) an ascorbic acid developing agent, (2) an auxiliary super-additive developing agent and (3) a carbonate buffering agent in a concentration of at least 0.5 molar. The developing solution is broadly useful in black-and-white development but is most advantageously employed in a process for forming a high-contrast image utilizing a silver halide photographic element comprising a hydrazine compound which functions as a nucleating agent and an amino compound which functions as an incorporated booster. The developing solution is ecologically advantageous, exhibits excellent stability with respect to seasoning effects, and provides high speed and good upper scale contrast combined with a low level of pepper fog and a moderate degree of chemical spread.

Abstract: A method for preparing 2-pyrazolin-5-ones from 1,2,4-oxadiazoles is described. The method comprises forming a liquid reaction system of a base catalyst and a 1,2,4-oxadiazole in an organic liquid reaction medium and heating the reaction system to a temperature sufficient to cause the 1,2,4-oxadiazole to be rearranged to a 2-pyrazolin-5-one.