Synthesis, characterization and application of antimicrobial functional dyes

In this study, a novel approach is proposed to achieve simultaneous dyeing and finishing of textile materials. The idea is to combine the traditional dyes and functional finishes together through suitable chemical linkages, and the whole structure may be regarded as a functional dye. It is expected that simultaneous dyeing and finishing can be achieved by simply following the traditional dyeing mechanisms by this approach.; To prove this concept, as an example, antimicrobial cationic dyes were designed and synthesized by incorporating tertiary amines into anthraquinone derivatives. The structures of the new dyes were fully characterized by FT-IR, 1H and 13C NMR analyses. The color features of the dyes were studied in terms of lambdamax and &egr; max in aqueous solutions, and the antimicrobial efficacy of the dyes were evaluated by using the minimum inhibitory concentration (MIC) as an indicator. To provide a practical guidance for these dyes in real applications, thermal and hydrolytic stabilities of these dyes were investigated. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were employed in the studying of thermal stabilities, and electron absorption spectra were used to evaluate the hydrolytic stabilities of the functional dyes at different pH values.; The performances of the dyes in the dyeing of acrylic fabrics, nylon fabrics, wool fabrics, and cationic dyeable polyester fabrics were investigated. In addition to visual observations, FT-IR results demonstrated that all these antimicrobial dyes could be incorporated into the fabrics by following traditional dyeing processes. The influences of dyeing conditions on the dyeing behaviors were explored in details. It was found that all the dyed fabrics exhibit antimicrobial activities. The durability of the antimicrobial functions was further studied.