Abstract: Heat-developable photothermographic materials capable of providing stable color images of high resolution. These materials comprise a support bearing a layer of an image-forming composition comprising:(a) a photosensitive silver halide,(b) an organic silver compound,(c) a reducing agent for silver ion, and(d) a binder,The reducing agent comprises a ballasted leuco dye compound. The ballasted leuco dye compound comprises a compound of the general formula:D--BwhereinD represents the reduced chromophore of a thermally mobile dye; andB represents an organic group that reduces the thermal mobility of D in the aforementioned binder, said organic group B capable of being oxidatively cleaved. The molecular weight of B must not be so high that the resulting amount of D in the emulsion layer is insufficient to yield a dye image having a reflection optical density of at least 0.3 or a transmission optical density of at least 0.2.

Abstract: A method of forming an image in which a color donor element and a receiving element are placed in face-to-face contact and opposed imagewise to infrared radiation, e.g. by laser exposure, in which at least one of the donor and receptor elements comprises a near-infrared absorbing dye which is a squarilium dye having dihydroperimidine terminal groups.

Abstract: A dye-transfer-sheet in the form of a self supporting film having a total thickness of from 4 to 15 .mu.m and consisting of a layer of one or more thermally mobile sublimation dyes dissolved or dispersed in a polymeric binder and a hydrophilic barrier layer adjacent to, but distinct from the dye-containing layer comprising a polymeric binder substantially impermeable to migration of the sublimable dye(s).The dye-transfer-sheets have a high sensitivity due to the absence of a separate support substrate and are capable of producing clear, high density transferred images.

Abstract: Compounds having a utility as photosensitive dyes in photocurable polymer based imaging systems having a nucleus of general formula (I): ##STR1## wherein: n is 1 or 2,Y is selected from the group consisting of 0 and ##STR2## Z is selected from the group consisting of 0.sup..crclbar. and ##STR3## M.sup..sym. is a cation.

Abstract: A photothermographic element comprising:(A) a coating comprising a support bearing a photothermographic medium, the medium comprising a light sensitive silver halide in reactive association with a silver salt of an organic acid and a color generating reducing agent which is a leuco compound which is oxidizable by silver ions into a colored dye of the general formula: ##STR1## in which: n=0, 1 or 2,R.sup.1 represents H, CN, lower alkyl of 1 to 5 carbon atoms, aryl or COOR.sup.6 in which R.sup.6 is lower alkyl of 1 to 5 carbon atoms or aryl,R.sup.2 and R.sup.3 independently represent CN, NO.sub.2, COOR.sup.6, SO.sub.2 R.sup.6, CONHR.sup.6 in which R.sup.6 is as defined above or R.sup.2 and R.sup.3 together represent the necessary atoms to form a 5- or 6-membered carbocyclic or heterocyclic ring having ring atoms selected from C, N, O and S atoms, whch carbocyclic or heterocyclic rings possess at least one conjugated electron withdrawing substituent,R.sup.4 and R.sup.

Abstract: A photothermographic element comprising a support bearing a photothermographic medium, the medium comprising a light sensitive silver halide in reactive association with a silver salt of an organic acid and a color generating reducing agent which is a leuco compound which is oxidisable by silver ions into a colored dye of the general formula: ##STR1## in which: n=0, 1 or 2,R.sup.1 represents H, CN, lower alkyl of 1 to 5 carbon atoms, aryl or COOR.sup.6 in which R.sup.6 is lower alkyl of 1 to 5 carbon atoms or aryl,R.sup.2 and R.sup.3 independently represent CN, NO.sub.2, COOR.sup.6, SO.sub.2 R.sup.6, CONHR.sup.6 in which R.sup.6 is as defined above or R.sup.2 and R.sup.3 together represent the necessary atoms to form a 5- or 6-membered carbocyclic or heterocyclic ring having ring atoms selected from C, N, O and S atoms, which carbocyclic or heterocyclic rings possess at least one conjugated electron withdrawing substituent,R.sup.4 and R.sup.

Abstract: Azine redox dyes and their corresponding dyes of the formula: ##STR1## in which: X is O, S, NR.sup.2,Z completes a fused aromatic of heterocyclic ring system,n is 0 or 1 to allow one R.sup.1 ring substituent,Q represents CR.sup.4 R.sup.5 in which at least one of R.sup.4 and R.sup.5 is an electronegative group or R.sup.4 and R.sup.5 may complete a ring, orwhen X is S Q may represent NR.sup.3 in which R.sup.3 is an aromatic or heterocyclic group.The leuco dyes are useful as dye generators in pressure sensitive, thermographic or photothermographic imaging systems.