N,N′-Disubstituted Naphthyl(Azo)-2,3-Dihydroperimidine Blue Dyes Exhibiting High Solubility in Ferroelectric Liquid Crystal Hosts

Abstract

The synthesis of N,N′-disubstituted naphthyl(azo)-2,3-dihydroperimidine blue dyes and a comparison of their absorption maxima and solubility in ferroelectric liquid crystal (FLC) hosts is described. The N,N′-disubstituted azo perimidines exhibited a much higher absorption maxima (20-50 nm) than their unsubstituted counterparts. In addition, the absorption maxima of the naphthyl(azo) perimidines was significantly higher than their phenyl(azo) analogues. Although the FLC solubility of the N,N′-dimethyl substituted dyes was similar to that measured for analogous unsubstituted dyes, the N,N′-dibutyl substituted bis(azo) dyes exhibited solubilities in excess of 8%.