Concurrent augmentation of acid dye affinity and antibacterial performance of viscose fabric via cationization

Purpose This study aims to explore the enhancement of acid dye-ability and antibacterial properties of viscose fabrics through cationization having different degree of amination (expressed as N %). Design/methodology/approach This was done by reacting the amine epoxide formed from epichlorohydrin and diethyl amine with viscose fabrics to obtain five levels of cationic viscose fabrics (CVFs) having different amine contents with increasing order and designated as (CVF-I - CVF-V). Characterizations via Fourier transform infrared spectroscopy and scanning electron microscopy of morphological surface change have been established in comparison with the untreated viscose fabric. Cationized viscose fabrics having different degrees of cationization were dyed with Acid red 88 to see their effect on the dyeing performance with respect to color strength and color coordinates as a colorimetric performance in addition to fastness performance to light, rubbing and washing. Findings The dyeing characteristics of the colorimetric data results revealed that the color strength was chiefly augmented from 1.85 to 3.44, and the notable improvement in colorimetric coordinate was also detected; in addition, the color fastness to light and rubbing was increased up to 2–3 and 3–4 in comparison with 1 for untreated viscose fabric by increasing the degree of cationization and following the order CVF V > CVF IV > CVF III > CVF II > CVF I. This is corresponded to the electrostatic interactions between the anionic acid dye and cationic viscose fabric functionality. Additionally, due to cationization, the estimated antibacterial efficacy was significantly increased for Staphylococcus aureus and Escherichia coli, respectively. Originality/value To the best of the authors’ knowledge, the novelty of this research lies in the ability to dye viscose with acid dyes via cationization, while originally these dyes are typically used mainly to color polyamide fibers.