Abstract: This invention relates to an organothiosulfonato Au(I) complex having the formula [A—SO2S—Au—SSO2—A]n−M+n wherein M is a cationic counter ion; A is a substituted or unsubstituted organic group; and n is 1 to 4; and wherein the compound is symmetrical. It further relates to the synthesis of said compounds.

Abstract: This invention relates to an organothiosulfonato Au(I) complex having the formula

Abstract: This invention relates to a photographic element comprising a support and a silver halide emulsion layer, the emulsion layer comprising a water soluble Au(I) complex having the formula [L—Au—L]n−M+n wherein the complex is symmetrical; L is an organothiosulfonato ligand which is an antifogging, stabilizing, or sensitizing compound, n is 1 to 4, and M is a cationic counterion. This invention further relates to a silver halide photographic element comprising a support and a silver halide emulsion layer, the emulsion layer comprising an organothiosulfonato Au(I) complex having the formula [A—SO2S—Au—SSO2—A]n−M+n wherein M is a cationic counterion; A is a substituted or unsubstituted organic group; and n is 1 to 4; and wherein the compound is symmetrical. It further relates to a method of preparing a silver halide emulsion utilizing said organothiosulfonato Au(I) complexes.

Abstract: This invention relates to an organomercapto Au(I) complex having the formula [(M—SOL)n—A—S—Au—S—A—(SOL—M)n]M wherein M is a cationic counterion; SOL is a solubilizing group: A is a substituted or unsubstituted divalent organic linking group; and n is 1 to 4 and wherein the compound is symmetrical. It further relates to a method of manufacturing an organomercapto Au(I) complex comprising reacting an Au (I) complex with an organomercapto ligand and isolating the resulting organomercapto Au(I) complex from the reaction mixture.

Abstract: A method of screening a water soluble gold complex for use as a sensitizer in a silver halide photographic element comprised of experimentally measuring the electrochemical potential of the gold complex and then determining if the electrochemical potential falls within a predetermined utility window.

Abstract: A method for preparing ultra-pure silver from a crude silver mixture containing metallic and/or non-metallic impurities, said method comprising; dissolving the crude silver mixture in nitric acid to form a crude silver nitrate solution; adding a first selective reducing agent to the crude silver nitrate solution to precipitate a silver/contaminant matrix and form a partially purified silver nitrate solution; separating the partially purified silver nitrate solution from the precipitated silver/contaminant matrix; adding a second selective reducing agent to the partially purified silver nitrate solution to precipitate silver powder; and isolating the silver powder.

Abstract: A method for preparing ultra-pure silver from a crude silver halide matrix containing metallic and/or non-metallic impurities, said method comprising; roasting the crude silver halide matrix to substantially remove carbonaceous material; treating the roasted crude silver halide matrix with ammonium hydroxide to dissolve the silver halides and form an ammonium hydroxide reaction mixture; adding an initial reducing agent to the ammonium hydroxide reaction mixture to precipitate a crude silver powder mixture; separating the crude silver powder mixture from the ammonium hydroxide reaction mixture dissolving the crude silver powder mixture in nitric acid to form a crude silver nitrate solution; adding a first selective reducing agent to the crude silver nitrate solution to precipitate a silver/contaminant matrix and form a partially purified silver nitrate solution; separating the partially purified silver nitrate solution from the precipitated silver/contaminant matrix; adding a second selective reducing

Abstract: The invention relates to a method of forming a silver halide emulsion comprising adding triiodide during grain formation or sensitization.

Abstract: This invention relates to an organomercapto Au(I) complex having the formula ##STR1## wherein M is a cationic counterion;SOL is a solubilizing group;A is a substituted or unsubstituted divalent organic linking group;and n is 1 to 4 and wherein the compound is symmetrical.It further relates to a method of manufacturing an organomercapto Au(I) complex comprising reacting an Au(I) complex with an organomercapto ligand and isolating the resulting organomercapto Au(I) complex from the reaction mixture.

Abstract: This invention relates to a silver halide photographic element comprising a support and a silver halide emulsion layer, the emulsion layer comprising an organomercapto Au(I) complex having the formula?(M--SOL).sub.n --A--S--Au--S--A--(SOL--M).sub.n !Mwherein M is a cationic counterion;SOL is a solubilizing group:A is a substituted or unsubstituted divalent organic linking group;and n is 1 to 4 and wherein the compound is symmetrical.It further relates to a method of preparing a silver halide emulsion utilizing said organomercapto Au(I) complexes.

Abstract: This invention relates to a silver halide photographic element comprising a support and a silver halide emulsion layer, the emulsion layer comprising a Au(I) compound having the formula wherein Z is a substituted or unsubstituted alkyl, aryl, alkylaryl, or heterocyclic group; and R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are independently substituted or unsubstituted alkyl, aryl, alkylaryl, or heterocyclic groups, or one or both of R.sub.1 and R.sub.2 or R.sub.3 and R.sub.4, may independently combine to form a nitrogen containing ring with the nitrogen to which they are attached.

Abstract: A photographic element comprising a support having situated thereon a silver halide emulsion layer, said emulsion layer comprising a compound of the formula:Z--S--Au(I)--S--Q (I)whereinZ represents an alkyl, aryl, or heterocyclic group; andQ represents a heterocyclic group wherein S and Q together represent a mesoionic group.

Abstract: This invention relates to a silver halide photographic element comprising a support and a silver halide emulsion layer, the emulsion layer comprising a Au(I) compound having the formula ##STR1## wherein Z is a substituted or unsubstituted alkyl, aryl, alkylaryl, or heterocyclic group; and R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are independently substituted or unsubstituted alkyl, aryl, alkylaryl, or heterocyclic groups, or one or both of R.sub.1 and R.sub.2 or R.sub.3 and R.sub.4, may independently combine to form a nitrogen containing ring with the nitrogen to which they are attached.

Abstract: A photographic element comprising a support having situated thereon a silver halide emulsion layer, said emulsion layer comprising a compound of the formula:Z--SO.sub.2 S--Au(I)--SQ (I)whereinZ represents an alkyl, aryl, or heterocyclic group; andQ represents an aryl or heterocyclic group.

Abstract: Ammonium pentachloromonoaquorhodate(III), (NH.sub.4).sub.2 RhCl.sub.5 (H.sub.2 O), is a useful photographic chemical. Small amounts of rhodium-containing, water soluble species remain in solution in the process liquor after synthesis. Most of the soluble rhodium values are present as the aforementioned ammonium complex; however there are traces of the cis and trans isomers of ammonium tetrachlorodiaquorhodate(III), and traces of the fac and/or mer isomers of rhodium(III) chloride triaquo complexes. Rhodium values present in the liquid as ammonium pentachloromonoaquorhodate(III) can be recovered by the addition of cesium chloride to form a precipitate identified as Cs.sub.2 RhCl.sub.5 (H.sub.2 O). Very little of the aforementioned fac and mer isomers or other contaminants, if any, are contained in the precipitate. The cesium rhodium pentachloride monohydrate product can be refined, for recovery of rhodium values, or used as an additive to a silver halide emulsion to control fog or stabilize the emulsion.

Abstract: Ultra-pure silver nitrate is prepared from crude silver by a process comprising the steps of dissolving the crude silver in nitric acid to form a crude silver nitrate solution; adding an alkaline agent, such as sodium hydroxide, to the crude silver nitrate solution to precipitate metallic contaminants and form a partially purified silver nitrate solution; adding a selective reducing agent, such as sodium formate, to the partially purified silver nitrate solution, to reduce silver nitrate to metallic silver and thereby precipitate silver powder while leaving metallic contaminants in solution; dissolving the silver powder in nitric acid to form a highly purified silver nitrate solution; and crystallizing ultra-pure silver nitrate from the highly purified silver nitrate solution.

Abstract: A process is disclosed for purifying a composition comprising at least one rare-earth element. The process is useful for removing radioactive impurities from these elements. The process comprises the steps of:(1) forming an aqueous solution of the composition to be purified having a pH between 4.0 and 6.5;(2) precipitating a portion of the rare earth and the radioactive impurities by adding to the solution, while maintaining the pH between 4.0 and 6.5;(i) a soluble barium or strontium salt;(ii) a soluble aluminum, magnesium or zirconium salt;(iii) a selective precipitating agent; and(iv) a sulfate ion-providing salt.The preferred selective precipitating agent is 8-hydroxyquinoline. After precipitation, the process is completed by the steps of:(3) separating the solution from the precipitate and(4) recovering purified rare earth from the solution.The process produces highly purified rare earth which can be used to form phosphors for X-ray screens.