Incorporation of Accessible Functionalities in Nanoscaled Coatings on Textiles Characterized by Coloration

Abstract

AbstractThe plasma‐assisted process presented in this paper facilitates the deposition of nitrogen containing functional coatings on textiles. Low pressure RF plasma was used to deposit multi‐functional thin films, which have a high amine content. Either acetylene or ethylene were mixed with ammonia to obtain a crosslinked structure that contained functional groups, which were accessible for dye molecules throughout the film volume. Varying deposition conditions were used in order to compare hydrocarbon gas mixtures in terms of deposition rates, water contact angles, aging, dyeability, yellowness index, and rub/wash fastnesses. The deposition rates were found to be higher for the acetylene discharges, but decreased with increasing ammonia‐to‐hydrocarbon ratios for both gas mixtures. Although this indicates etching effects, a permanent hydrophilization could still be obtained. These findings demonstrate that plasma polymerization provides an eco‐friendly multi‐functionalized surface modification, since the use of chemicals, waste water etc. can be eliminated. Dyeing of the plasma coatings by acid dyestuffs showed that the relative color strength value, i.e. amine functionalities, can be noticeably enhanced, while being strongly influenced by the energy input and by the gas ratio. It was evident that the coating quality could be improved significantly using an ammonia/ethylene plasma due to reduced unsaturated bonds, the latter being investigated by the CIELAB color spaces. A high dyeing fastness indicated a strong dye‐molecule bonding, which in turn, is an indication of permanency of the amine groups. A pilot‐scale web coater at Empa was used to demonstrate the feasibility of industrial scale‐up.magnified image