Photographic products and processes

Abstract

Abstract THE PRESENT INVENTION RELATES TO PHOTOGRAPHY AND, MORE PARTICULARLY, TO REFLECTION TYPE DIFFUSION TRANSFER PROCESS PHOTOGRAPHIC FILM UNITS WHICH COMPRISE A COMPOSITE PHOTOSENSITIVE ELEMENT ADAPTED TO PROVIDE, BY DIFFUSION TRANSFER PHOTOGRAPHIC PROCESSING, SELECTIVE INTEGRAL NEGATIVE AND POSITIVE IMAGE RECORDATION OF INCIDENT ANTINIC RADIATION AS A FUNCTION OF THE POINT-TO-POINT DEGREE OF PHOTOSENSIVE ELEMENT EXPOSURE, WHICH INCLUDES A PLURALITY OF SEQUENTIAL LAYERS INCLUDING A PHOTOSENSIVE SILVER HALIDE LAYER HAVING ASSOCIATED THEREWITH IMAGE-FORMING MATERIAL WHICH IS PROCESSING COMPOSITION DIFFUSIBLE AT A FIRST PH AS A FUNCTION OF THE POINT-TO-POINT DEGREE OF SILVER HALIDE LAYER EXPOSURE TO INCIDENT ACTINIC RADIATION, A LAYER ADAPTED TO RECIEVE IMAGE-FORMING MATERIAL DIFFUSING THERETO, AND WHICH ADDITIONALLY INCLUDES MEANS FOR PROVIDING AT LEAST ONE OPTICAL FILTER AGENT AT A PH ABOVE THE PKA OF THE OPTICAL FILTER AGENT WHOSE PKA IS BELOW SAID FIRST PH IN A CONCENTRATION EFFECTIVE TO PROVIDE, IN SITU, A LAYER EXHIBITING OPTICAL TRANSMISSION DENSITY SUFFICIENT TO PROVIDE A BARRIER WITH RESPECT TO INCIDENT VISIBLE RADIATION SUBSEQUENT TO PHOTOEXPOSURE OF THE SILVER HALIDE LAYER AND MEANS FOR REDUCING THE INITIAL PH OF THE LAYER TO A SECOND PH BELOW THE PKA OF THE OPTICAL FILTER AGENT, WHICH PH IS ABOVE THE PH NECESSARY FOR DIFFUSION OF SAID IMAGEFORMING MATERIAL AND, SUBSEQUENT TO SUBSTANTIAL TRANSFER IMAGE FORMATION IN THE RECEPTION LAYER, REDUCING THE PH TO A THIRD PH WHEREIN THE IMAGE-FORMING MATERIAL IS NONDIFFUSIBLE. D R A W I N G

Inventors

• 👤 T Milligan

Bibliographic Details