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Folium artemisiae argyi (FAA) leaves have a long history of usage as a food colorant throughout China, but their usage as a biocolorant for textile substrates has not been fully exploited yet. The present research focused on the extraction of functional components of FAA leaves and their applications for simultaneous coloration and biofunctionalization of wool fabrics. Examination of different extracting solvents (ethanol/water combinations); identification and stability of color components using UV–vis, FT-IR, TG, and DTG; and examination of dyeing methods were successfully carried out during the course of this work. Additionally, the dyes extracted in different solvent systems were subjected to total phenolic and flavonoid content analysis and expressed as gallic acid and catechin equivalents, respectively. The different solvent extracts (50% aqueous ethanol in conjunction with small amounts of acid and alkali) gave the maximum biocolorant yield at 80 °C for 60 min. Wool fabrics dyed in different solvent systems gave different colors with good washing fastness. The inadequate fastness characteristics were evidently ameliorated by premordanting with Fe2+ and Al3+ salts. An adequate amount of FAA leaf extract on wool fabrics exhibited good UV protection, antibacterial, and antioxidant behaviors. Premordanting enhanced UV protection, antibacterial, and antioxidant behaviors of dyed wool fabrics. Wool fabrics treated with FAA leaf extracts exhibited diverse color variations (such as green color with alum mordant) and proved to be greatly promising for industrial application as a source of natural biocolorants, as well as a value-adding application for the plant in addition to its normal usage as a food colorant.

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The utilisation of ultrasonics has been shown to enable efficient and environmentally friendly textile wet processing. This study conducted a comparative investigation of silk degumming by using a conventional heating bath and ultrasonic irradiation at a range of ultrasonic frequencies. Citric acid, sodium carbonate and papain were used as degumming agents. Sericin degumming rate, fibre whiteness, fibre surface morphology, fibre structure characteristics and fibre tensile properties were measured and analysed. Results showed that ultrasonics at a lower frequency produced a greater degumming rate than at a higher frequency. Ultrasonics is a more effective way than the conventional heating bath of improving degumming efficiency, especially at a lowered temperature of 60°C. When sodium carbonate was applied at 90°C, a conventional heating bath was found to be more effective than ultrasonics. Papain was found to be more effective in sericin removal than citric acid and sodium carbonate, with a degumming rate of 22% achieved at 60°C under ultrasonic irradiation at 40 kHz. The use of papain can, however, cause a possible overreaction to silk under certain severe conditions, resulting in a loss of fibre whiteness. Negligible changes in fibre structure characteristics were measured by Fourier Transform-infrared spectroscopy and X-ray diffraction after ultrasonic degumming with papain. Slightly reduced fibre strength and increased fibre extensibility were observed in ultrasonically degummed silk samples compared with un-degummed and conventionally degummed silk samples.

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