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Published on: June 12, 2018
Application of different concentrations of the natural dye potassium norbixinate (annatto) in polyamide 6.6 fabrics
Marcel Jefferson Gonçalves1,2, Ariane Canuto Veiga de Oliveira2, Amábile Colla Prando2
1Postgraduate Program in Environmental Engineering, Regional University of Blumenau (FURB), Blumenau, Brazil.
Abstract:
Polyamide fabrics were dyed with concentrations ranging from 4% to 0.25% (o.w.f.) of the natural dye, potassium norbixinate (annatto). The exhaustion, chromatic coordinates, colouristic intensity (K/S), and fastness to washing and rubbing were evaluated. The natural dye was characterised, and its maximum absorption peaks were identified at 452 nm and 482 nm through UV-vis scanning. Its main chemical groups were identified by FTIR-ATR. All dyeings exhibited high exhaustion percentage, with a maximum of 98.4% for 1% dye concentration. The dyed samples displayed visually appealing orange hues, with a maximum K/S value of 6.9. Most of the fastness test results were rated between 5 and 4/5, remaining within the standards established by most textile industries. Potassium norbixinate exhibited a similar tinctorial behaviour to synthetic acid dyes for polyamide, suggesting ionic chemical reaction interaction between dye and polyamide, highlighting the potential use in the textile industry.
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