HYDRAZIDE COMPOUNDS USEFUL AS CO-DEVELOPERS FOR BLACK-AND-WHITE PHOTOTHERMOGRAPHIC ELEMENTS

Trityl hydrazides and formyl-phenyl hydrazines are useful as co-developers with hindered phenols in thermographic elements. These co-developers have the formula: R -(C=O)n-NHNH-R R represents hydrogen and R represents an aryl or substituted aryl group; or, R represents hydrogen, alkyl and alkenyl groups of up to 20 carbon atoms; alkoxy, thioalkoxy, or amido groups of up to 20 carbon atoms; aryl, alkaryl, or aralkyl groups of up to 20 carbon atoms; aryloxy, thioaryloxy, or anilino groups of up to 20 carbon atoms; aliphatic or aromatic heterocyclic ring groups containing up to 6 ring atoms; carbocyclic ring groups comprising up to 6 ring carbon atoms; or fused ring or bridging groups comprising up to 14 ring atoms; and R represents a trityl group. The thermographic elements in the present invention may be used as a photomask in a process where there is a subsequent exposure of an ultraviolet or short wavelength visible radiation sensitive imageable medium.