Photothermographic recording material comprising a hydrazine compound

Abstract

A photothermographic recording material comprising a support and a photo-addressable thermally developable element containing a substantially light-insensitive organic silver salt, a reducing agent therefor in thermal working relationship therewith, photosensitive silver halide spectrally sensitized with a dye and in catalytic association with the substantially light-insensitive organic silver salt and a binder, wherein the photo-addressable thermally developable element further includes a hydrazine compound represented by the formula (I): ##STR1## wherein: Z represents the necessary atoms to close a heterocyclic ring which is either a five-membered ring containing at least two heteroatoms or a six-membered ring, which ring may carry one or more fused-on rings, and which ring must contain a C--H bond permitting oxidative aromatisation to an acyl-onium group by means of a hydride shift or a consecutive 2-electron-proton transfer; each of R.sup.1 and R.sup.2 independently represents a hydrogen atom or an alkali-labile group giving rise to a hydrogen atom on hydrolysis; X is an acyl group selected from the group consisting of CO--R.sup.3, CS--R.sup.4, PO--R.sup.5 R.sup.6 and (CN--R.sup.7)--R.sup.8, wherein each of R.sup.3 to R.sup.8 independently represents alkyl, aryl, cycloalkyl, heterocycloalkyl, heteroaryl, O-alkyl, O-aryl, O-heteroaryl, O-heterocycloalkyl, S-alkyl, S-aryl, S-heterocycloalkyl, S-heteroaryl or N--R.sup.9 R.sup.10, wherein each of R.sup.9 and R.sup.10 independently represents hydrogen, aryl, alkyl, heteroaryl, heterocycloalkyl or acyl as defined for X, and wherein R.sup.5 together with R.sup.6, and R.sup.9 together with R.sup.10 may represent the necessary atoms to close a ring.