Dyeing silk and cotton fabrics using Fuji apple peel and the properties of the dyed fabrics

A new source of natural dyes, which possessed antibacterial and UV protection properties, was proposed. Natural dyes were extracted from Fuji apple peel. The extract contained two anthocyanins and five quercetin glycosides. Silk and cotton fabrics were dyed using the extract with and without six types of mordants: Mg2+, Ca2+, Al3+, Ti4+, Fe3+, and Cu2+. The properties of the dyed fabrics were investigated by various means. The K/S values were used to show relative color strength of the dyed fabrics and the CIELAB color system was used to show the color hue of the dyed fabrics. The crystallinity of the silk was lower than that of the cotton. The silk was dyed deeper than the cotton regardless of the dyeing conditions, including dyeing temperature, dyeing period, and solution pH. This result comes from the existence of carboxyl and amino groups and low crystallinity of silk fibers. Fabrics with various colors, including pink, green, brown, and gray, were obtained by mordant dyeing. The dyed fabrics had splendid performance; that is, antibacterial and UV shielding properties. Color fastness to washing (color change) was comparably low but was enhanced with Ti4+ and Fe3+ mordants.

Application of natural dyes from selected indigenous plants on cotton and silk fabrics

Standard procedures for mordant dyeing were used to dye plain weave cotton and silk fabrics with dye from four selected indigenous plants viz: A. coriaria, V. paradoxa, M. lucida and H. madagascarensis. Alum and ferrous sulphate mordants were with the following mordanting methods; pre, simultaneous and post mordanting. Color fastness was used as a basis to evaluate the performance of each method. Color strength imparted on fabric was used as a basis to optimize the following selected dyeing variables viz: temperature, dyeing time, material to liquor ratio (M:L), and mordant concentration (o.w.f). Mordant dyeing under optimized conditions improved color strengths and fastness on both cotton and silk fabrics. According to the optimized variables, silk fabrics required a little more heating (80˚C to 95˚C) for a longer time (≈ 1hr 30mins) than cotton to achieve optimal strengths of color. The fastness obtained for various fastness characteristics on both fabrics dyed under optimized conditions varied from fairly good (3) to excellent (5) with cotton giving better fastness. However, silk recorded better color strength in term of k/s values in the range of (110 to 260) and more lustrous appearance was observed on it. Dye from M. lucida plant species recorded overall superior color characteristics on both fabrics and with both mordants.

Acute toxicity tests and dyeing potentials of three azo dyes from Pyocyanin, produced by Pseudomonas aeruginosa from farmlands

The admiration for colours by man has made dyes to have very useful applications on a great variety of materials. Pyocyanin (PCN) or 5-methyl-1-hydroxyphenazine, a phenazine derivative biosynthesized by Pseudomonas aeruginosa isolated from the stressed soil of a farmland at Awka was used to prepare three azo dyes namely, pyocyanin azophenol, pyocyanin azo-1-naphthol and pyocyanin azo-2-naphthol. The PCN was treated with SOCl2 to convert it to the chloro analogue. Treatment of chloro analogue with NaCN in ethanol and subsequent acid hydrolysis gave the carboxylic acid from which the amide was obtained after treatment with (NH4)2CO3 and heat. The amide was converted to the amine by Hoffman’s amide degradation. The amine was diazotized and coupled with phenol, 1-naphthol and 2-naphthol to give the three azo dyes respectively. UV-VIS and infrared spectra of the compounds agreed with the assigned structures. Acute Toxicity (LD50) tests showed the compounds to be reasonably non-toxic. Dyeing potentials of the Pyocyanin (PCN), PCN azophenol, PCN azo-1-naphthol and PCN azo-2-naphthol by mordant dyeing on cotton, silk and nylon textile materials showed them to have blue, dark green, purplish-brown and red colours respectively. The dyes were reasonably fast to light, washing, rubbing, alkali and acid. Pyocyanin, Pyocyanin azophenol, Pyocyanin azo-1-naphthol and pyocyanin azo-2-naphthol produced from Pseudomonas aeruginosa isolated from farmland soil can be used effectively to dye cotton, silk and nylon textile materials.

Tannin-Mordant Coloration with Matcha (camelia sinensis) and Iron(II)-Lactate on Human Hair Tresses

The aim of this work was to optimize our natural hair dyeing system which we described in our previous work and to compare with other dyeing systems. Therefore, we investigated concentration limits of matcha and mordant and compared this new dyeing method with commercial permanent systems on the market. Completely unpigmented hair tresses were dyed with matcha powder (camelia sinensis) and iron(II)-lactate. To investigate the wash fastness and concentration limits, the differently dyed hair tresses were spectrophotometrically measured. The comparison of the damage potential for which cysteic acid is an indicator was measured by NIR. The concentration of matcha and mordant are responsible for the intensity of the color results. The higher the matcha or the mordant concentration, the darker the color results of the dyed hair tresses. Hair damage of matcha mordant dyeing is comparable with results of commercial permanent hair coloration systems. Moreover, the results of wash fastness of matcha mordant dyed hair tresses is comparable and even better by tendency to permanent colored hair tresses.

APPLYING BI–FUNCTIONAL DYEING AND UV PROTECTION ON PROTEIN TEXTILE MATERIALS WITH WASTE FROM USED TEABAGS AND MANGOSTEEN HULLS

This paper presents the connection among three factors of the eco–friendly approach and products: natural textile materials, natural dyes and utilization of waste. The silk and wool materials were chosen as they are both protein fibers that have natural dyes affinity. The dyes were extracted from wastes (mangosteen hulls and used tea–bags) with optimal conditions found during our experiments: 80 °C for 120 min with a 15 % w/v citric acid solution in a 1:10 ratio of mangosteen flakes to solvent and 100 °C for 60 min in a 1:20 ratio of spent tea powder to solvent. The silk dyeing and wool dyeing were carried out at separately proper temperature, time and concentrations. The effect on dyeing of mordant types with different salt–metals mordanting methods and mordant techniques – pre–mordanting, simultaneous mordanting and post–mordanting were undertaken. The K/S values were used for determining the fixation of dyes on textile materials as it reflects the surface luster shade of the dyeing products. The results helped to estimate the influence of dyeing processes on protein materials where low temperature (< 90 °C) and post–mordanting methods exhibited good effects. The UPF values above 29 measured on dye fabric proved the excellent UV protection, even with non–mordant dyeing.