Evaluación de la calidad del hilo de alpaca (Vicugna pacos) teñido con diferentes tintes naturales a distintos valores de ph

Abstract

The growing environmental concern and associated risks with chemical dyes have driven a renewed interest in natural dyes within the textile industry. For this reason, the primary purpose of this research is to evaluate the impact of different natural dyes at various pH levels on alpaca (Vicugna pacos) yarns made from fleece categorized as semi-fine. This research is experimental and follows a bifactorial design, with the first factor being the pigment source: purple cabbage (Brassica oleracea var. capitata f. rubra), qolli flower (Buddleja coriacea), and alder bark (Alnus glutinosa); and the second factor being different pH levels: 3,5, 5,5, and 7,5, resulting in nine treatments. Each treatment followed three replications with an experimental unit size of 200 grams. The Bromatology and Animal Nutrition Laboratory and the Specialized Tannery Laboratory of the Faculty of Animal Sciences – ESPOCH were essential scenarios to develop this study. The physical properties of the yarn (tensile strength, percentage elongation, lightfastness, wash fastness, and rub fastness) were evaluated, along with a sensory assessment. Analysis of Variance (ANOVA) and Tukey's post-hoc test, were essential for data analysis. The findings revealed significant differences among treatments, showing impacts on wash fastness and dry and wet rub fastness, with the lowest scores of 4,67, 3,00, and 3,67, respectively, observed with alder bark at pH 7,5. In the case of sensory evaluations, the findings did not show any significant impact on properties like roughness or itchiness in dyed yarns. Other properties like tensile strength, percentage elongation, and lightfastness did not show any significant change either. The lowest production cost resulted in purple cabbage at different pH levels due to the availability of this pigment source. Finally, pigment source selection and pH are remarkable factors based on the specific color attributes desired in the yarn.