Photochromatic Materials in the Graphic Arts.

Photochromatic materials are light-activated, form images without wet or vapor processing, are reversible, i.e. can be erased and reused, and exhibit selective spectral absorption and very high resolution. These characteristics suggest many applications of photochromatics to the graphic arts. Several examples are: production of temporary positives or negatives, control of tone reproduction, and contrast enhancement. Tone control is of special interest, and is discussed in some detail.