Abstract: A non-volatile passive memory element comprising on a single surface a first electrode system and a second electrode system together with an insulating system, unless the insulating system is the surface, wherein the first electrode system is insulated from the second electrode system, the first and the second electrode systems are pattern systems and at least one conductive or semi-conducting bridge is present between the first and second electrode systems, and wherein the non-volatile passive memory device is exclusive of metallic silicon and the systems and the conductive or semiconducting bridges are printable using conventional printing processes with the optional exception of the insulating system if the insulating system is the surface. A non-volatile passive memory device comprising a support and on at least one side of the support the above-mentioned non-volatile passive memory element.

Abstract: A recording material for producing high contrast images comprising at least one thermosensitive element, comprising a layer comprising a substantially light-insensitive organic silver salt in at least one binder and in thermal working relationship therewith an organic reducing agent therefor, on a support, characterized in that the recording material is light-insensitive and the layer contains colloidal particles comprising silicon dioxide at a coating weight given by expression (1): ##EQU1## wherein B represents the total weight of all binders in the layer, AGOS represents the total weight of organic silver salt in the layer and S represents the weight of the colloidal particles in the layer; and wherein a protective layer is optionally applied to the thermosensitive element being thereby an outermost layer of the recording material.