Material for use in a photographic reproduction system

Claim 1

A MATERIAL CAPABLE OF FURNISHING A RECORD SOLELY IN THE FORM OF A DISTRIBUTION PATTERN OF RADIATION SCATTERING DISCONTINUTIES FORMED WITHIN AN OTHERWISE SUBSTANTIALLY HOMOGENEOUS VEHICLE, SAID MATERIAL COMPRISING A SUPPORTING FILM OF POLYETHYLENE TEREPHTHALATE HAVING A SURFACE COATING OF DRY, WATER-RESISTANT, NON-HYGROSCOPIC THERMOPLASTIC VINYLIDENE CHLORIDE POLYMER, SAID POLYMER HAVING A LIGHT-DECOMPOSABLE, SOLID DIAZONIUM COMPOUND SUBSTANTIALLY UNIFORMLY DISPERSED THEREIN AS THE SOLE IMAGE PRODUCING AGENT, SAID DECOMPOSABLE AGENT ITSELF BEING NON-REACTIVE TO SAID POLYMER AND UPON EXPOSURE TO LIGHT DECOMPOSING INTO PRODUCTS WHICH ARE ALSO CHEMICALLY NON-REACTIVE TO SAID POLYMER AND WHICH UPON WARMING ARE VOLATILE TO FORM SAID RADIATION SCATTERING DISCONTINUITIES ONLY IN THE LIGHT STRUCK AREAS IN SAID POLYMER TO THEREBY FURNISH SAID RECORD, SAID MATERIAL BEING PREPARED BY THE STEPS OF: PREPARING A UNIFORM MIXTURE OF SAID POLYMER AND DIAZONIUM COMPOUND IN NON-AQUEOUS ORGANIC SOLVENT, COATING SAID MIXTURE DIRECTLY UPON SAID SUPPORTING FILM AND THEN DRYING THE THUS COATED FILM TO OBTAIN SAID MATERIAL.