Structure - color Correlation Study in the Class of Pre-formed Acid Azo Chromium (1:1) Complex Dyes Containing the Sulfonic Group in the Diazotation Component

This paper aims to explain the variation of (UV-Vis) spectral parameters of pre-formed azo chromium (1:1) complex dyes, containing the sulfonic group in the diazotation component, having aryl-azo-pyrazolone and aryl-azo-naphtaline type structures, (aryl=benzene, naphtaline) versus spectral parameters of (1:1) chromium complex of azo dyes (A): 2-aminophenol-4-sulphonic acid → acetoacetanilide and (B): 1diazo-2-naphtol-4sulphonic acid ® acetoacetanilide, considered as reference structures, taking into account the electronic effects (σ, π) of substituents.