Dyeing Properties Of Wool Fabrics Research Articles

Natural dyeing of air plasma‐treated wool fabric with Rubia tinctorum L. and prediction of dyeing properties using an artificial neural network

AbstractIn this study, the ecological dyeing process of wool fabrics was investigated. Wool fabric samples were treated with atmospheric pressure plasma‐jet and corona discharge plasma to modify the surface to make the process sustainable and greener. The samples were dyed with the aqueous extract procured from the powdered roots of Rubia tinctorum L. (madder) using the ultrasonic‐assisted method. Scanning electron microscopy and Fourier Transform–infrared analysis were performed to investigate the effect of plasma treatment on the physical and chemical properties of wool fibres. The effects of plasma treatment type, plasma treatment parameters and the duration of dyeing on colorimetric and fastness properties were investigated. The etching of the wool fibre surface and roughness after plasma treatment were proven with scanning electron microscopy images. The Fourier Transform–infrared spectra showed that no significant differences in the functional groups of wool fibre occurred after plasma treatment. The experimental results proved that plasma treatment parameters and dyeing time had an effect on the colorimetric and fastness properties of the samples. Furthermore, an artificial neural network model was proposed for estimating the dyeing properties of wool fabrics, namely, L, a, b, K/S, colour change, rubbing fastness (dry) and rubbing fastness (wet). The experimental results show that the proposed model achieves regression values greater than 0.97 for all dyeing properties. The proposed model is successful and can be efficiently used for estimating the dyeing characteristics of wool fabrics.

Investigation of the dyeing properties of wool fabrics with Alkanna tinctoria root extract

In this work, dyeing properties of wool samples with Alkanna tinctorum root extract was investigated. For this purpose, two different dyestuff extracts, red and blue are gained from its roots with acetone and ethanol solvents, as well. Wool fabrics (194 pieces) dyed with AIK(SO4)·12H2O, FeSO4·7H2O, CuSO4·5H2O, AgNO3 and CoCI2·6H2O mordants at pH 2, 4, 6 and 8, respectively. Unmordanting, pre-mordanting, meta-mordanting, and post-mordanting methods were used for the dyeing experiments. In addition, wool fabrics were pretreated with artificial animal urine system (AAUS) including NH3 (3%, v/v), CaC2O4 (3%, m/v) and urea (3%, m/v) before dyeing processes in order to see the improvement in the fastness properties of the dyed samples with meta-mordanting method. The color codes were determined with Pantone Color Guide, and also washing-, rubbing fastness levels were evaluated using gray scale. According to the evaluations, it is observed that AAUS mordant system helps to improve the light fastness values in general. Good results were obtained both for the dyeings with red and blue components, as well. Optimum dyeing parameters were also evaluated for wool fabric in terms of usage in textile industry.

UV Protection and Dyeing Properties of Wool Fabrics Dyed with Aqueous Extracts of Madder Roots, Chamomiles, Pomegranate Peels, and Apple Tree Branches Barks

ABSTRACT This paper studies the dyeing properties of wool fabrics dyed with aqueous extracts of madder roots, chamomiles, pomegranate peels, and apple tree branches (obtained after pruning) barks. We have thoroughly investigated the effects of dye bath pH and mordants on the color properties of the aforementioned fabrics. Even without mordanting, the wool fabrics dyed with the pomegranate peel have the highest value of color strength (K/S = 14). Mordanting permits to produce different colors and improve the fastness of a dye, especially for madder roots, chamomile, and apple tree branches bark. UV protection of wool fabrics increased after natural dyeing, and it was more improved after mordanting especially with ferrous sulfate. Experimental results show that the fastness properties of dyed wool fabrics range from average to excellent even without mordanting.

Effect of laccase on dyeing properties of polyphenol-based natural dye for wool fabric

Chemical mordants are generally used during the dyeing process, to increase the uptake of natural dyes. Traditional mordants include metal salts, such as copper, iron, aluminum, chromium, and other metal ions. Continuous developments in bio-engineering technology focus on methods that lower the impact on the environment. In this regard, enzymatic processes show great promise in textile field, due to their efficacy, mild conditions, and environment friendly nature. Laccase is a multicopper oxidoreductase that catalyzes in-situ polymerization of small phenolic monomers to form a colorful polymer. In this study, effects of laccase treatment on the dyeing properties of wool fabrics, dyed with natural dyes (turmeric, grape seed extract, and Chinese gallnut), were investigated. The dyeing properties of the dyed wool fabrics were evaluated under different conditions, including laccase stoichiometry, temperature, pH, and reaction time. The structural changes of natural dyes, due to laccase catalyst were also examined by FT-IR. The results showed that laccase greatly influenced the dyeing performance of Chinese gallnut. Moreover, dyeing effects of the samples using post-mordanting method was better than the other two methods, under the same conditions. After laccase treatment, the dyeing properties of Chinese gallnut improved. Finally, factors affecting the dyeing process with Chinese gallnut were studied and the optimized conditions were determined through single-factor experiments.

Study of dyeing properties of wool fabrics treated with microwave

Wool was pretreated with microwave and then dyed with Lanasol reactive dye and Palatin 1:1 metal complex dye by conventional exhaust dyeing process. Adsorption behaviour and diffusion coefficient were also studied. A higher dye uptake rate and increased diffusion coefficient of treated fibres are observed in the dyeing test after microwave pretreatment, but the adsorption behaviour remains constant. Microwave pretreatment has a slightly damaging effect on the surface scale-like structure of wool, which results in the reduction of the concentration of S–S bonds in keratin. It was considered that the surface damage improved the absorption of dye molecules by the wool fibres during dipping and the diffusion of dye molecules into the wool fibres.

Study on the dyeing of wool fabrics with Phytolacca berry natural dyes

Dyeing of wool fabrics with natural dyes from Phytolacca berries has been studied. The effect of dye concentration, dye bath pH, dyeing time and temperature were discussed. The influence of chitosan application on the dyeing properties of wool fabrics was investigated. The SEM photographs of chitosan treated wool fabrics clearly depict the deposition of chitosan on the fibers. The effect of chitosan concentration, dye bath pH, dyeing time and temperature has been studied by orthogonal experiment. It has been proved that the dyed wool samples pretreated by chitosan have higher color fastness, faster dyeing rate, and better antibacterial properties compared with untreated ones.

Modification of Wool Fabric to Improve Its Dyeability

A study of pretreatment of wool fabric with chitosan and some natural constituents of lemongrass oil as citral and nerol has been carried out. The pretreatments effectively enhanced the dyeing properties of wool fabrics. Pretreatments with chitosan improve the dye ability, color fastness, whiteness, and the wet ability. Citral and nerol are used as properfumes fabric treatment and surfactant and cleaner to fabrics. These products are also resistant to laundering, and they are suitable for environmentally friendly treatments of wool fabric. Chemical and mechanical measurements of the treated samples compared with the untreated one are reported.

Transglutaminase treatment for improving wool fabric properties

The microbial transglutaminase (mTGase) is used as a bio-catalyst to repair the wool damages caused by chemical or enzymatic treatments. In this paper, the effect of mTGase on the degree of yarn strength, area shrinkage, wettability, and the dyeing properties of wool was investigated. Through mTGase treatment, the yarn strength was improved about 22.2 %. The knitted wool fabrics treated with mTGase after pretreatment of H2O2 and protease displayed 7.5 % of area shrinkage and about 22.3 % recovery in tensile strength when compared with those treated without mTGase. Also, mTGase treatment could improve the wettability and dyeing properties of wool fabrics. With the increase of mTGase concentration, the initial dye exhaustion increased significantly and the time to reach the dyeing equilibrium was shortened. It was evident that the improvement of dyeing properties was closely related to the improvement of wettability performance of wool fabric by using transglutaminase.

Effect of protease treatment on dyeing properties of wool fabrics for single bath

During the conventional process of dyeing for wool fabric, the most important problem is the damage to wool fiber and energy waste because of high temperature. In this paper, the effect of a commercial protease, Savinase 16L from Novozymes, on low temperature dyeing properties of wool fabric was studied. The results showed that after treatment with protease for 30 min at 50°C and pH 8.0, the exhaustion of the Acid Yellow 116 on wool fabric increased 11.11% and 8.58% by comparing with that on the control samples without protease treatment when dyeing at 80°C and 90°C, respectively. And the dye absorption at 90°C on protease pretreated wool fabric was almost the same as that with the conventional boiling dyeing procedure. A single bath process containing protease treatment at 50°C and pH 8 and dyeing at 90°C and pH 4 was investigated. The dyeing effect of wool fabric dyed with one-bath process was nearly the same as that with the two-bath method and conventional boiling dyeing process. The results suggest that protease treatment offers an option of a one-bath dyeing process, replacing the water- and energy-consuming two-bath method and conventional dyeing process.

Dyeing and antimicrobial characteristics of chitosan treated wool fabrics with henna dye

Chitosan, a naturally available biopolymer which is now increasingly being used as a functional finish on textile substrates to impart antimicrobial characteristics and increase dye uptake of fabrics was applied on wool fabrics. Henna a natural dye with proven bactericidal properties was applied on wool fabrics along with chitosan to impart antimicrobial characteristics. The effect of chitosan application on the dyeing properties of wool fabrics was studied by measuring the K/ S values of the treated substrates at various concentrations of chitosan and the dye. The antimicrobial properties of chitosan and natural dyes both when applied independently and collectively on fabrics were assessed. The results proved that the chitosan treated wool fabrics showed increase dye uptake of fabrics. The treated fabrics were found to be antimicrobial and the chitosan treatment enhances the antimicrobial characteristics of the dyes. Fastness properties of the applied finish to washing, rubbing and perspiration have also been discussed.