4-Hydroxypyrazole developing agents
AssigneePolaroid Corporation
InventorRichard B. Greenwald
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Abstract
Certain 4-hydroxypyrazoles are employed as silver halide developing agents which find particular utility in diffusion transfer photographic processes.
Claims23
A method of developing a silver halide emulsion which comprises treating an exposed silver halide emulsion layer carried on a support with an aqueous alkaline processing composition of a silver halide developing agent of the formula ##STR3## wherein R.sup.1 is selected from hydrogen and hydroxy and R.sup.2 and R.sup.3 each is selected from phenyl, 2-thienyl and alkyl.
A photographic product comprising a support, a silver halide emulsion carried on said support and a developing agent in a layer on the same side of said support as said silver halide emulsion, said developing agent having the formula ##STR10## wherein R.sup.1 is selected from hydrogen and hydroxy and R.sup.2 and R.sup.3 each is selected from phenyl, 2-thienyl and alkyl.
Dependencies are inferred from the claim text.