Laccase-catalysed coloration of wool and nylon

The potential for laccase (EC 1.10.3.2) to be used within the area of textile coloration, specifically for the generation of decorative surface pattern design, remains relatively unexplored. The current study presents a novel process for the coloration of wool and nylon 6,6 fibres via laccase oxidation of aromatic compounds as an alternative to conventional dyeing methods. Emphasis was placed on producing a diverse colour palette, which was achieved through the investigation of three different aromatic compounds as laccase substrates: 1,4-dihydroxybenzene, 2,7-dihydroxynapthalene and 2,5-diaminobenzenesulphonic acid. Reaction processing parameters such as buffer systems and pH values, laccase and aromatic compound concentrations, and reaction times were investigated, all in the absence of additional chemical auxiliaries. Enzymatically dyed fabrics were tested against commercial standards, resulting in reasonably good colour fastness to wash. To demonstrate the coloration and design potential by laccase catalysation of aromatic compounds, specially constructed fabrics using a combination of undyed wool, nylon and polyester yarns were dyed using the one-step laccase-catalysed coloration process. The use of different fibre types and weave structures enabled simple colour variations to be produced. Shadow, reserve and contrasting effects were achieved with the laccase-catalysed dyeing process developed. Important advantages over conventional processing methods include the use of simpler and milder processing conditions that eliminate additional chemical use and reduce energy consumption.