Photographic material and process

Claim 1

IN THE PROCESS OF PRODUCING A PHOTOGRAPHIC DYE IMAGE FROM A PHOTOGRAPHIC MATERIAL HAVING AT LEAST TWO LIGHT SENSITIVE HALIDE EMULSION LAYER EACH SENSITIVE FOR LIGHT OF ONE OF AT LEAST TWO DIFFERENT PREDETERMINED SPECTRAL REGIONS, AND EACH OF SAID TWO LAYERS CONTAINING A DIFFERENT PH SENSITIVE AZO DYE, EACH OF SUCH PH SENSITIVE AZO DYES BEING IN TRANSMITTITANT FROM AT THE SAME PH TO LIGHT WAVES OF THE REGION TO WHICH THE LAYER CONTAINING SUCH DYE IS SENSITIVE, AND ABSORBENT FOR SUCH LIGHT WAVES AT ANOTHER PH, EACH OF SAID DYES BEING ABSORBENT AT THE SAME LAST MENTIONED PH, EACH OF SAID DYES HAVING THE FORMULA A-N=N-B WHEREIN A IS AN AROMATIC RADICAL CARRYING AN ELECTROPOSITIVE SUBSTITUENT IN POSITION 4 WITH RESPECT TO SAID AZO GROUP, SAID SUBSTITUENT BEING A MEMBER POF THE GROUP CONSISTING OF HYDROXY, AMINO, ARYLATED AMINO, ALKYLATED AMINO AND ORGANIC SULFONIC ACID ACYL AMINO GROUPS, AND B IS AN AZO COUPLING COMPONENT RADICAL SELECTED FROM THE GROUP CONSISTING OF AROMATIC RADICALS CARRYING AN ELECTRONGATIVE SUBSTITUENT OF THE GROUP CONSISTING OF NITO, SULF, SULFONE, SULFAMIDE, CARBOXYLIC ACID, CARBOXYLIC ESTER, CARBOXYLAMIDE,NITRILR,VINYL AND AZO GROUPS, AND A PYRAZOLONE RADICAL, THE STEPS WHICH COMPRISE EXPOSING SUCH PHOTOGRAPHIC MATERIAL TO LIGHT WHILE THE LAYERS CONTAINING THE PH SENSITIVE AZO DYES ARE AT A PH WHICH IS COMPATIBLE WITH THE LIGHT SENSITIVE SILVER HALIDE EMULSION AND AT WHICH EACH OF SUCH DYES IS SUBSTANTIALLY TRANSMITTANT TO THE IGHT WAVES TO WHICH THE LAYER CONTAINING SUCH DYE IS SENSITIVE, FORMING A DYE IMAGE IN SAID TWO EMULSION LAYERS FROM SAID PH SENSITIVE AZO DYES, AND AT A POINT AFTER THE EXPOSURE OF SUCH MATERIAL, ADJUSTING THE PH OF SAID EMULSION LAYERS IN THE SAME DIRECTION TO A PH AT WHICH SUCH DYES ARE SUBSTANTIALLY ABSORBENT TO THE LIGHT WAVES TO WHICH SAID TWO EMULSION LAYERS WERE SENSITIVE DURING EXPOSURE TO CAUSE THE DYES IN THE DYE IMAGE TO BE IN SUCH ABSORBENT FORM.