| abstract |
Photochemical systems for the visualization of exposure to ultraviolet radiation and for the utilization of ultraviolet radiation to effectuate visible color changes involving a process responsive to ultraviolet radiation in which a photoacid is formed upon irradiation of a photoacid progenitor compound with ultraviolet light and wherein proton transfer to a dyestuff causes the dyestuff to undergo a visible color change. If desired, the system undergoes such color changes to an extent directly proportional to the cumulative amount of ultraviolet incident thereupon. Examples are given of materials which can be made into films, extruded into fibers, formed into objects, or formulated as inks, paints, and the like. |