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Felting shrinkage of wool is a major problem which has negative impacts on its performance attributes. Traditional chemical methods used for shrink-resist finishing are suffering from some drawbacks. Therefore, this work aimed at the utilization of microbial protease in wet processing of wool. The bacterial strain Bacillus licheniformis ALW1 produced 52.1 U/mL enzyme activity that was thermophilic with optimum activity at pH 9. Additionally, the enzyme possessed a keratinolytic activity of 4.1 U/mL, suggesting its applicability in wool processing. Therefore, the effects of different treatment conditions; Viz. concentration of the enzyme, temperature, treatment period and pH on some of the physical and chemical characteristics of wool were studied. The felting shrinkage of wool fibers was determined using the Aachener 3-D felting machine. The influence of the enzymatic modification of wool on its dyeability with anionic dye was assessed. Chemical, physical, and mechanical properties of treated samples were evaluated using amino acid analysis, alkali solubility, Fourier Transform Infrared spectroscopy, whiteness index, and tensile properties. Scanning electron microscopy was applied for the examination of wool fibers’ surface. The results proved that the modification of wool fibers with the produced enzyme highly improved their felting resistance and dyeability with acid dye without adverse effects on its inherent properties.

Although their favorable performance, appearance, and comfort attributes, woolen garments have the tendency to felt unenviably during washing. In this work, an eco-friendly, energy-saving, non-deteriorative process for the fabrication of machine-washable wool tops (WTs) was proposed. WTs were exposed to atmospheric air or an argon plasma treatment at different powers for various durations, followed by coating with a protein biopolymer, namely keratin, using the pad-dry-cure technique. The felting resistance of the finished WTs was evaluated, and the results revealed that the finished sample has an enhanced felting resistance to the extent of machine-washable wool (no felt ball is formed), whereas the untreated sample forms a felt ball with a diameter of 2.166 cm after undergoing the felting test. The treated WTs maintained their felting resistance after 20 wash cycles. The surface composition of the plasma-treated WTs was examined using X-ray photoelectron spectroscopy. The change in the chemical structure of the treated WTs was monitored by determining the cystine content, alkali solubility, base-combining capacity, and affinity to anionic dye. The dye exhaustion of the untreated and finished samples after 60 min was 66% and 98.8%, respectively. Scanning electron microscopy was used to study the wool fibers’ topography.