A thermally developable material comprising a support and having thereon at least one thermally developable imaging layers comprising in reactive association at least one non-photosensitive source of reducible silver ions, at least one reducing agent for said reducible ions, at least one binder comprising vinyl butyral repeat units and vinyl alcohol repeat units, and at least one crosslinker comprising an isocyanate group, where the thermally developable material has a composition that exhibits an equivalent weight ratio of the vinyl alcohol repeat units in the at least one binder to the isocyanate groups in the at least one crosslinker of at least 75.