Opaque permeable polymeric layer in photo-sensitive element

Claim 1

A PHOTOGRAPHIC FILM UNIT WHICH IS ADAPTED TO BE PROCESSED BY PASSING SAID UNIT BETWEEN A PAIR OF JUXTAPOSED PRESSURE-APPLYING MEMBERS AND WHICH COMPRISES, IN COMBINATION: A PHOTOSENSITIVE ELEMENT COMPRISING A COMPOSITE STRUCTURE CONTAINING, AS ESSENTIAL LAYERS, IN SEQUENCE, A FIRST DIMENSIONALLY STABLE TRANSPARENT LAYER, A PHOTOSENSITIVE SILVER HALIDE EMULSION LAYER HAVING ASSOCIATED THEREWITH A DYE IMAGE-FORMING MATERIAL WHICH IS SOLUBLE AND DIFFUSIBLE, IN ALKALI, AT A FIRST PH, AN ALKALINE SOLUTION PERMEABLE OPAQUE LAYER, AN ALKALINE SOLUTION PERMEABLE POLYMERIC LAYER DYEABLE BY SAID DYE IMAGE-PROVIDING MATERIAL, AN ALKALINE SOLUTION PERMEABLE POLYMERIC ACID LAYER CONTAINING SUFFICIENT ACIDIFYING GROUPS TO EFFECT REDUCTION OF A PROCESSING SOLUTION HAVING SAID FIRST PH TO A SECOND PH AT WHICH SAID DYE IMAGE- PROVIDING MATERIAL IS SUBSTANTIALLY INSOLUBLE AND NONDIFFUSIBLE, A SEOCND DIMENSIONALLY STABLE TRANSPARENT LAYER, AND MEANS SECURING SAID LAYERS IN FIXED RELATIONSHIP, AND A RUPTURABLE CONTAINER RETAINER AN ALKALINE PROCESSING SOLUTION, HAVING SAID FIRST PH, FIXEDLY POSITIONED AND EXTENDING TRANSVERSE A LEADING EDGE OF SAID PHOTOSENSITIVE ELEMENT TO EFFECT UNIDIRECTIONAL DISCHARGE OF THE CONTAINER''S CONTENTS BETWEEN SAID ALKALINE SOLUTION PERMEABLE AND DYEABLE POLYMERIC LAYER AND THE PHOTOSENSITIVE SILVER HALIDE EMULSION LAYER NEXT ADJACENT THERETO UPON APPLICATION OF COMPRESP SIVE FORCE TO SAID CONTAINER.