THE BEHAVIOR OF NONIONIC DYES AND SURFACTANTS IN FOAM DYEING SYSTEMS (LOW WET PICK-UP, TOPICAL METHODS, STABILITY, POLYESTER, FABRICS)

The purpose of this study was to investigate the behavior of simple foam dyeing systems containing nonionic dyes and surfactants. The factors influencing foam dyeing and its application to woven polyester fabrics were also examined.; Dye dispersions of known particle size distribution and dispersant content were prepared from purified Disperse Red-60 and Disperse Blue-79 presscake. The Du Nouy ring method was used to study the surface tension behavior of aqueous surfactant solutions. Measurements were performed on nonionic lauryl alcohol and nonylphenol surfactants of different ethylene oxide chain length in the absence and presence of various solution additives. A transition to higher surface tension and CMC values was observed for all the systems. The surface activity of these solutions was found to be inversely proportional to the CMC.; The foam stability of different foam systems was found to be dependent on the bulk viscosity of the solution. This effect reduces the two drainage rates occurring in the foam, drainage due to gravity and capillary drainage. The inclusion of a foam stabilizer in the formulation enhanced foam stability but also accentuated any defects present in the fabric or occurring during processing.; Foams were applied to woven polyester fabrics with a knife applicator. The foam layer was collapsed by passing the fabric over a vacuum slot. Dye fixation was accomplished by thermosoling the foam-dyed fabrics.; A two-constant model was found which explains the drainage behavior of the different foam systems reasonably well. Both constants provide indirect information concerning the drainage rates of the foam and the uniformity and coverage of the foam-dyed fabrics.; The fastness properties of the fabrics were not adversely affected by the surfactant type used to generate the foam and were equivalent to those usually obtained with conventional dyeing methods.