Vesicular type photographic materials comprising a polyurethane resin containing light decomposable compounds

Claim 1

A RECORD FURNISHING MATERIAL CAPABLE OF FURNISHING A RECORD SOLELY IN THE FORM OF A DISTRIBUTION PATTERN OF RADIATION SCATTERING DISCONTINUITIES FORMED WITHIN A VEHICLE WHICH IS OPTICALLY SUBSTANTIALLY HOMOGENEOUS, SAID MATERIAL BEING IN THE FORM OF A DRY, WATER-RESISTANT, NONHYGROSCOPIC FILM HAVING A PERMEABILITY CONSTANT FOR NITROGEN WITHIN THE RANGE OF 8.6X10**-16 AND 8X10**-10, SAID CONSTANT BEING THE NUMBER OF CUBIC CENTIMETERS OF NITROGEN TRANSMITTED AT 30*C., BY AN AREA OF ONE SQUARE CENTIMETER IN ONE SECOND WHEN THE PRESSURE GRADIENT IS ONE CENTIMETER OF MERCURY PER ONE CENTIMETER OF TRANSMISSION THICKNESS, THE CONTINUOUS PHASE OF SAID FILM BEING ESSENTIALLY A PREFORMED SYNTHETIC, HOMOGENEOUS NON-FOAMED WATER-INSOLUBLE HYDROPHOBIC, THERMOPLASTIC POLYURETHANE RESIN AND A LIGHT DECOMPOSABLE SOLID AGENT SUBSTANTIALLY UNIFORMLY DISPERSED IN SAID FILM AS THE SOLE ESSENTIAL IMAGE PRODUCING AGENT, SAID DECOMPOSABLE AGENT ITSELF BEING SUBSTANTIALLY NON-REACTIVE TO SAID VEHICLE AND UPON EXPOSURE TO LIGHT DECOMPOSING INTO PRODUCTS WHICH ARE ALSO CHEMICALLY SUBSTANTIALLY NON-REACTIVE TO SAID VEHICLE AND WHICH SOLELY UPON WARMING ARE VOLATILE TO FORM SAID RADIATION SCATTERING DISCONTINUITIES ONLY IN THE LIGHT STRUCK AREAS IN SAID FILM HAVING THE INDICATED PERMEABILITY TO THEREBY FURNISH SAID RECORD.