Reversible redox-controlled imaging method

摘要

A novel class of N-substituted triarylmethane sulfonamides is provided which undergo reversible oxidation into colored form and reversible reduction of the oxidized form into colorless form. Preferred embodiments comprise xanthene sulfonamides having N-aryl substituents, e.g., hydroquinone substituents. These compounds possess redox potentials ranging between about +200 to -500 millivolts and thus are useful as dyes for producing photographic, photothermographic, thermal, and pressure-induced images, as well as being useful as redox indicators in a wide variety of biological and chemical reactions.