The improvement of dyeability of flax fibre by urea treatment

Abstract

PurposeThe purpose of this paper is to improve the dyeability of flax fibre by modification via urea treatment and to explore the mechanism of such improvement.Design/methodology/approachThe modification to the flax fibre was carried out with different concentrations of urea solution, then the optimum condition for the dyeability improvement was investigated by the measurement of the dyeing colour depth. The chemical properties of the raw and the treated flax fibres were characterised using a variety of techniques including Fourier transform‐infrared spectroscopy analysis and X‐ray photoelectron spectroscopy analysis.FindingsIt was found that the dyeability of flax fibre had been significantly improved via urea treatment. The mechanism of the improvement of the dyeability of the flax fibre was found to be due to the amino groups (NH2) introduced to the flax fibres during urea treatment, which increased the activity of the reaction between the dye and the fibre compared to hydroxyl groups of raw flax fibre.Practical implicationsThe treatment method developed provided a practical and effective solution to poor dyeability of flax fibre.Originality/valueThe method could be adapted for use in industrial scale flax dyeing with satisfactory levels of exhaustion and fixation.