Abstract: A photosensitive element which comprises on a support at least one photosensitive silver halide emulsion layer and at least a non-light sensitive layer, wherein the silver halide emulsion layer comprises a chalcogenic compound satisfying formula (1): ##STR1## wherein: X represents Se or Te, forming a double bond with its neighbouring C-atom,Nu represents a nucleophilic group which brings an electron pair in heterolytic bond formation; Nu has a pK.sub.a -value of at least 2.0 if Nu is an acidic group,L represents a divalent linking group representing each group which can position an electron donating atom in any of the 5th to the 8th position vis-a-vis the carbon atom of the carbon-chalcogen double bond,AQB represents the necessary atoms to form a heterocyclic 5- or 6-membered ring, provided that when A is a Nitrogen-atom, B is an atom selected from the group consisting of NR.sup.1, O, S, Se and Te,R.sup.

Abstract: A method is disclosed for preparing silver halide emulsions useful in photography. Said method comprises the step of precipitating silver halide grains in an aqueous solution of peptizer initially and finally under pAg values suitable for forming cubic silver halide crystals characterized in that at least once during the precipitation stage the pAg is increased for at least 10 percent by weight of the total amount of silver salt used during the precipitation by at least 1.5 units to such value whereby the formation of octahedral crystals would occur if that value were to persist over the entire precipitation stage.Preferably the increase of the pAg value is brought about after precipitation of between ten and twenty percent of the total amount of silver halide to be precipitated.

Abstract: A method for processing an imagewise exposed photographic silver halide emulsion material using a receptor element for complexed silver halide which element contains a stabilizing agent corresponding to one of the following general formulae (I) or (II), tautomeric structures or a precursor form thereof: ##STR1## wherein: X represents hydrogen, alkali metal, ammonium or organic amine,Z represents the non-metallic atoms necessary to form a 5- or 6-membered heterocyclic nucleus, andeach of R.sup.1 and R.sup.2 (same or different) represents hydrogen, amino, alkyl, alkenyl, cycloalkyl, aryl, alkoxy, alkylthio, alkylsulfonyl, sulfamoyl, acyl, --SH or a heterocyclic group.

Abstract: The present invention provides a dye diffusion transfer imaging process comprising transferring image-wise by diffusion an acid dye to an image-receiving layer incorporating a non-polymeric phosphonium mordanting agent and a copolymer latex comprising free weak acid groups as a stabilizer for the mordanting agent, wherein the image-wise transfer of said acid dye is performed in the presence of a heterocyclic compound corresponding to one of the following general formulae I, II, and III: ##STR1## wherein: Y represents the non-metallic atoms needed to complete a saturated or unsaturated 5- or 6-membered heterocyclic nucleus, which may carry a fused-on aromatic ring system, and M represents hydrogen, an alkali metal atom, a quaternary ammonium group, or a negative charge forming an inner salt with a quaternized nitrogen atom of the heterocyclic compound. The invention also provides an image receptor element for dye diffusion transfer imaging processes comprising a support and such image-receiving layer.

Abstract: A process for the production of a sealed laminate especially a security document comprising a support sheet, an image layer containing a photographic image present in a hardened hydrophilic diffusion transfer reversal image-receiving colloid medium made from an image receiving layer containing photosensitive iron(III) compound, and a protective cover sheet is described wherein:(1) the support sheet is of a polymeric heat meltable material,(2) the image layer is disposed adherently on the support sheet to cover the support area only partly and to leave uncovered at least one edge area thereof,(3) the protective sheet is of a heat-meltable material which in the melted state is capable of forming a homogeneous mass with melted support sheet material, and(4) the protective cover sheet is heat sealed to the support sheet in the uncovered areas thereof to form the homogeneous mass, whereby said image layer is sealed between the support sheet and the protective sheet.