Abstract: Disclosed is a system for developing latent images on alkali-based or acid based paper stock which has been marked with a water-soluble oxidizing agent to form a concealed image. In the system, a marking composition is applied to said paper stock which comprises(a) A water-soluble iodide,(b) Acetic acid,(c) A water-soluble reducing agent, and(d) Water.Preferably, the reducing agent is ascorbic acid and preferably the marking composition also comprises a water-soluble dye.

Abstract: Disclosed is a system for developing latent images on alkali-based or acid-based paper stock which has been marked with a water-soluble oxidizing agent to form a concealed image. In the system, a marking composition is applied to said paper stock which comprises(a) A water-soluble iodide,(b) Acetic acid,(c) A water-soluble reducing agent, and(d) Water.Preferably, the reducing agent is ascorbic acid and preferably the marking composition also comprises a water-soluble dye.

Abstract: A cyanide-free desensitizing or conversion solution for converting imaged electrophotographic masters to lithographic printing plates comprising:(a) from about 1.0 to about 3.0 percent of phytic acid;(b) from about 0.5 to about 2 percent of a water-soluble anionic polymer;(c) from about 1.0 to about 3.0 percent of a water-soluble dibasic acid; and(d) an aqueous carrier; all percentages being based upon the total weight of the solution, the pH of said solution ranging from about 3.5 to about 6.0.A method of using this solution to convert imaged masters is also disclosed.