The assembly of rotaxane-like dye/cyclodextrin/surface complexes on aluminium trihydroxide or goethite†‡
Rachel J. Cooper,Philip J. Camp,Ross J. Gordon,David K. Henderson,Dorothy C. R. Henry,Hamish McNab,Sonali S. De Silva,Daniel Tackley,Peter A. Tasker,Paul Wight
Dalton Transactions Pub Date : 05/05/2006 00:00:00 , DOI:10.1039/B518260C
Abstract

Simple azo-dyes carrying phosphonic acid and arsonic acid substituents such as 4-(4′-hydroxyphenyl azo)phenylphosphonic acid (5) and 4-(4′-hydroxyphenylazo)phenylarsonic acid (6) bind more strongly to high surface area oxides such as aluminium trihydroxide and goethite than their carboxylic and sulfonic acid analogues and the phosphonate-functionalized dyes have been shown to have greater humidity fastness when printed onto commercial alumina-coated papers. Adsorption isotherm measurements provide evidence for the formation of ternary dye/cyclodextrin/surface complexes. Dyes which form such ternary complexes show higher light fastness when printed onto alumina coated papers in an ink formulation containing α-cyclodextrin.

Graphical abstract: The assembly of rotaxane-like dye/cyclodextrin/surface complexes on aluminium trihydroxide or goethite