The correlation of Hammett substituent and Brownstein solvent constants with photochromic properties of triarylmethane dye leucocyanides

Abstract

Five triarylmethane leucocyanides were synthesized from their parent dyes, and a photochromic test apparatus was designed and fabricated. The leucocyanides were tested for sensitivity and fade time in six solvents. The data was found to correlate well with Hammett substituent constants and with Brownstein solvent coefficients with certain exceptions