Dyeing of wool with Marigold and its properties

This research work involves the dyeing of wool with Marigold as a source of yellow colour. To do this, wool yarns pre-treated with Alum as a colorless mordant, dyed with Marigold and then treated with different percentages of ammonia solutions. The chromaticity co-ordinates of samples measured in CIELAB system. TheL* values of all ammonia treated samples decreased and the values ofa*,b*,C* dependent on the ammonia solution. It can also indicate that the reflectance spectrum of treated samples decreases due to ammonia treatment. The rate of vertical wicking decreases on Marigold dyed treated with ammonia. Color hue of the Marigold dyed wool alters after washing with standard soap and ammonia after-treatment has no influence on washing fastness. The samples dyed with Marigold and after-treated with ammonia show a lower light fastness.     

A comparative study on wool bio-antifelting based on different chemical pretreatments

The enzymatic antifelting of wool with proteases, which is referred to as bio-antifelting, has become a promising eco-friendly alternative to conventional chlorination treatment. However, wool bio-antifelting in industrial scale has not been reached so far due to its unsatisfactory shrink-resistance and uncontrolled action in fiber damage. In this paper, the action and mechanism of two kinds of chemical pretreatments, i.e., hydrogen peroxide and dichlorodicyanuric acid pretreatments on the shrink-resistance of protease-treated wool fabrics were investigated and compared. The results show that although hydrogen peroxide treatment could decrease the shrinkage of wool in comparison with untreated one, its contribution to the enhancement of wool bio-antifelting with protease was not remarkable. An effective shrink-resistance can be obtained when the wool fabric was treated with dichlorodicyanuric acid and protease consecutively. Both of the two chemical pretreatments could improve the wettability and whiteness of protease-treated wool. The mechanism of different pretreatments for enhancing wool bio-antifelting with protease was further illustrated and compared via several microscopic analyses such as Allwörden’s reaction, FTIR-ATR and SEM. The comprehensive comparison for wool bio-antifelting based on different chemical pretreatments reveals the difference of hydrogen peroxide and dichlorodicyanuric acid pretreatments in antifelting mechanism, which is valuable for getting a clear understanding and further modification of wool bio-antifelting.     

A study of the oxygen plasma treatment on the serviceability of a wool fabric

Low temperature plasma (LTP) treatment using oxygen gas was applied to a wool fabric. The LTP treated wool fabric was tested with several methods: ASTM D5035-1995, ASTM D1424-1996, AATCC Test Method 99-2000, AATCC Test Method 61-2001 1A, AATCC Test Method 15-2002 and AATCC Test Method 8-2001 and the results were compared with the industrial requirements (ASTM D3780-02 and ASTM D4155-01). The results revealed that the LTP treated wool fabric could fulfil the industrial requirements. The results of the investigation were discussed thoroughly in this paper.     

Effect of wool surface modification on fluorocarbon chain re-orientation

There is an increasing demand for air-dry performance of fluorocarbon finished materials. Thus, surface modifications of wool fabrics were evaluated. Untreated, gaseous fluorinated, Chlorine/Hercosett processed 100 % wool fabrics were treated with different fluorochemicals and their liquid repellency after washing, and dry cleaning were evaluated. The results indicated that Chlorine-Hercosett treated samples, wool with a positive charge, after few washing cycles, showed better air dry performance with higher level of repellent properties. In addition, the comparison of the wool surface modifications treatment with different applied fluorochemicals, with different commercial formulations, illustrated that the fluorocarbon chain re-orientation and fastness properties are more affected by the nature of the wool surface while the used fluorocarbons showed more or less similar behaviours. In general, the fluorination increases fabric stiffness with lower fabric formability. The surface interface was effectively probed by X-ray Photoelectron Spectroscopy, XPS, which enabled the characterisation of the loss of surface lipids, the nature of the fibre oxidation and the deposition of fluoropolymers.     

Union dyeing of the photografted PET/wool blend fabrics with dimethylaminopropyl methacrylamide

Dimethylaminopropyl methacrylamide (DMAPMA) was grafted onto PET/wool blend fabrics by continuous UV irradiation. Union dyeing of the photografted fabrics was investigated using three reactive dyes of α-bromoacrylamide reactive groups. The influence of grafting yield, DMAPMA concentration, NaCl amount, pH value, and dyeing temperature on the dyeability was evaluated. The dyeability of both PET and wool components was improved significantly by the DMAPMA photografting and successive reactive dyeing. Although the dyeability of the PET component in the blend substantially was improved with higher grafting, equal dyeability between PET and wool was difficult to achieve due to more facile grafting and higher reactivity of the wool component compared with the modified PET component. However, the color fastness of the PET/wool blend fabric was excellent for all three colors. This study may offer a way to achieve union dyeing of PET/wool blend fabrics.     

Study on the natural dyeing of wool modified with enzyme

In this study, the natural pigment from sappan was used for the dyeing of wool fabrics after treatment with the protease and transglutaminase. The influences of protease and transglutaminase on the UV/visible absorption spectrum of aqueous extract of sappan were studied. The enzymatic modified wool was compared with non-modified wool in K/S value and fastness after direct dyeing and mordant dyeing. It was shown that protease and transglutaminase made the absorbance at the λ _max 540 nm in visible region increase. It suggested that there might be some interaction between the enzymes and sappan dye and the residual enzyme on wool fabric might affect the color of following dyeing. Compared to untreated wool, treatments with protease and transglutaminase enhance K/S value of wool dyed subsequently with sappan. Modification of protease led to some decrease in wet rubbing fastness, whereas transglutaminase had almost no influence on rubbing fastness. Enzymatic treatments have no influence on the washing fastness for samples dyed with sappan.     

Extraction, identification and dyeing studies of Isosalipurposide, a natural chalcone dye from Acacia cyanophylla flowers on wool

A chalcone compound Isosalipurposide 1 was qualitatively isolated from Acacia cyanophylla yellow flowers. The dyeing of wool fabrics with this chalcone compound as a natural dye has been studied. The effect of dye bath pH and dyeing temperature were investigated. The obtained shades were bright with generally a good fastness. A post-mordanting method was used in the dyeing of wool with this chalcone dye. It was found that, generally, mordanting improved light fastness especially in the case of zinc sulphate.     

Surface characterization of low temperature plasma treated wool fiber

Previous investigation results revealed that after the Low Temperature Plasma (LTP) treatment, the hydrophilicity of wool fiber was improved significantly. Such improvement enhances the wool dyeing and finishing processes which might be due to the changes of the wool surface to a more reactive one. In this paper, wool fibers were treated with LTP with different gases, namely, oxygen, nitrogen and gas mixture (25 % hydrogen/75 % nitrogen). Investigations showed that chemical composition of wool fiber surface varied differently with the different plasma gas used. The surface chemical composition of the different LTP-treated wool fibers was evaluated with different characterization methods, namely FTIR-ATR, XPS and saturated adsorption value. The experimental results were thoroughly discussed.     

Preparing fluorescent wool/acrylic blends with a hemicyanine reactive cationic dye

Wool/acrylic blends were dyed with a hemicyanine reactive cationic dye, Dye 1, to prepare the fluorescent wool/acrylic blends in this article. The study initially focuses on the optical properties of Dye 1, followed by dyeing properties of Dye 1, then ended with fluorescent properties of the dyed wool/acrylic blends. The results show that the exhaustion, fixation, and fastness to washing and rubbing of Dye 1 on wool, acrylic, and wool/acrylic blend were good throughout. The dyed wool/acrylic blends can emit obvious fluorescence. In addition, according to the EN-1150 standard (1999), the chromaticity of dyed wool/acrylic blends meet the requirements of fluorescent pink when the dye concentrations are suitable.     

One-Bath Union Dyeing of Wool/Acrylic Blend Fabric with Cationic Reactive Dyes Based on Azobenzene

Three unreported cationic reactive dyes based on azobenzene were synthesized using a novel synthetic route. Synthesized dyestuffs containing three primary color dyes were characterized by FTIR, H-NMR, LC-MS, Element Analysis and UV-vis spectroscopic techniques. The absorption spectra of dyes were measured in three solvents with different polarities. The dyeing and color fastness properties of three cationic reactive dyes on wool, acrylic and wool/acrylic blend fabrics were determined. The optimum pH for wool and acrylic fabrics were 6 and 5, respectively. Effect of temperature, time on dyeing properties and color fastness properties on wool fabric showed the same tendency with acrylic fabric. The K/S value of wool fabric dyed with three dyes was similar to that of acrylic fabric when both fabrics were dyed simultaneously in the same dyebath using low dye concentration. Wool/acrylic blend fabric dyed with three cationic reactive dyes using onebath one-step method achieved good union dyeing property and excellent color fastness.     

Dyeing properties and colour fastness of wool dyed with indicaxanthin natural dye

This research work involves the dyeing of wool with indicaxanthin, a natural dye extracted from fruits of Opuntia ficus-indica. The optimal conditions for dye extraction were to mix 50 g of Juice from cactus pears with 100 mL of 80% aqueous ethanol as solvent for dye extraction. Liquid chromatography was applied for the separation. Two main dyes were obtained, which were identified as indicaxanthin (75 mg per 50 g) and betanin (5 mg per 50 g). The effect of dye bath pH, salt concentration, dyeing time and temperature were studied. The optimal conditions for wool dyeing with indicaxanthin dye were carried out at 70 °C for 90 min with the pre-treatment of various metal salts as mordant. The colour yields of the dye on the wool were found to be highly dependent of the pH, optimum results being obtained at pH 4. The K/S of wool increased in the order of the dyeing using KAl (SO₄)₂ > MnSO₄ > CoSO₄ > FeSO₄ > none > ZnSO₄ > CuSO₄. Un-mordanted samples have good properties of water and washing fastness. Mordants KAl (SO₄)₂ and CoSO₄ were found to give good light fastness (rating 5).     

The effect of carbon black nanoparticles on some properties of air plasma printed cotton/polyamide 6 fabrics

In this study, cotton/nylon blended fabrics were treated with atmospheric air plasma at various times (30–60 s) and were subsequently printed with pastes containing carbon black nanoparticles. Properties of plasma treated fabrics such as visible-near infrared (Vis-NIR) reflectance, water contact angle, air permeability, and color fastness were measured. It was shown that increasing plasma treatment time decreases reflection level of treated fabrics in Vis-NIR region. Plasma treatment also enhanced the hydrophobicity of cotton/nylon fabrics observed by an increase in water contact angle. Plasma treated samples for 60 s demonstrated lower air permeability than those treated for 30 s. Furthermore, printed samples possessed acceptable levels of fastness against washing, light and crocking.     

Fast response photochromic textiles from hybrid silica surface coating

In this study, a hybrid silica sol-gel embedded with a photochromic dye has been applied to wool fabric to form a photochromic coating. The treated wool fabrics showed very quick photochromic response. Five different silanes have been used as the silica precursor, and the resultant coating showed slight differences in photochromic performance, fabric washing fastness, and surface hydrophilicity. However, the silica type had a considerable influence on fabric handle property. The silica matrix from the silane containing a long alkyl chain had a very little influence on the fabric handle and better photochromic performance than those from other different silane precursors.     

UV-grafting coloration of cotton and wool fabrics using bismethacrylated quinizarin dye

A novel bifunctional quinizarin dye possessing two photoactive methacrylate groups was synthesized by the reaction of quinizarin with methacryloyl chloride. The synthesized dye, a low substantive dye under the conventional dyeing process, can be photografted onto cotton and wool fabrics at room temperature without neutral salts, which makes it a novel coloration process of excellent environmental friendliness. The concurrent polymerization and grafting of the synthesized dye onto cotton or wool can be assisted by a photoinitiator and acrylic acid in the case of cotton grafting. Moreover, color yields of the grafted fabrics improved significantly with the photografting of the bifunctional dye. The bifunctional dye can be photopolymerized with the increase in UV energy to 25 J/cm² and the oligomeric dye has a degree of polymerization of 5 or more. Furthermore, the color fastness properties of the grafted fabrics were superior to those of the dyed fabrics via exhaustion.     

Dyeing, fastness, and deodorizing properties of cotton, silk, and wool fabrics dyed with gardenia, coffee sludge, Cassia tora. L., and pomegranate extracts

Four kinds of natural dying solutions (natural colorant extracts) were obtained by extraction from gardenia, coffee sludge, Cassia tora. L., and pomegranate using water at 90°C for 90 min with a liquor ratio (solid natural colorant material/solvent water, weight ratio) of 1/10. The dyeing, colour fastness, and deodorizing properties of cotton, silk, and wool fabrics dyed with natural colorant extracts were compared. It was found that these properties were significantly dependent on the concentration of extracts, the structure of colorant, and the kind of fabrics. The order of colour strength (K/S) is Cassia tora. L., pomegranate, coffee sludge, and gardenia. Colour fastness (light, water, and perspiration fastness) was in the range of 2nd–5th grades. The deodorizing performance of fabrics dyed with various natural colorant extracts was in the range of 50–99 %. The deodorizing performance increased in the order of gardenia < Cassia tora. L. < coffee sludge < pomegranate. Especially, the deodorizing performance of all fabrics dyed with pomegranate was found to be highest at 99 %.     

A comparative evaluation of the action of savinase and papain to the cutinase-pretreated wool

The enzymatic anti-felting of wool with proteases is a promising eco-friendly alternative to the chlorine-Hercosett process. However, protease molecules could penetrate into the interior of fibers during wool processing, easily causing unacceptable damages. In this paper, the action and mechanism of two protease treatments, i.e. Savinase and papain treatments on the properties of cutinase-pretreated wool fabrics were investigated and compared. The results showed that the anti-felting processing based on cutinase and papain treatments seemed more effective. When the percentages of weight loss for the combined treated fabrics were similar, the improvement of wettability and shrink-resistance for the cutinase-papain treated sample was more remarkable, the strength loss was also lower than that of the sample treated with cutinase and Savinase consecutively. The mechanisms of the two different combined treatments were further evaluated by Allwöden’s reaction and amino acid analysis. The comprehensive comparison proved that the hydrolytic activity of papain towards the scale exocuticle of wool was a bit higher than that of Savinase and less degradation of the interior of fibers occurred during the cutinasepapain treatment.     

Dyeing properties of wool fabrics dyed with Vitis Vinifera L. (black grenache) leaves extract

In this work, water-extraction of Vitis Vinifera L. (Black Grenache) leaves and analysis of aqueous extracts for anthocyanins were investigated. Vegetable leaves were cultivated in North of Tunisia at different dates. Anthocyanins were identified as main constituents in these natural dyeing materials using high performance liquid chromatography (HPCL). Dyeability of wool and its fastness properties using Vitis Vinifera L. leaves extract were also determined. Aqueous extract of Vitis Vinifera L. leaves has markedly yielded shades with good fastness properties. Thus, affordability is a point favorable for Vitis Vinifera L. leaves. Effects of dye bath pH and temperature on dyeability and fastness proprieties of wool fabrics by aqueous extract of Vitis Vinifera L. leaves were evaluated. Experimental results showed that fastness properties of dyed fabrics ranged from average to very good. Vitis Vinifera L. leaves extracts showed potential to dyeing wool fibers under highly acidic conditions (pH ≤2). The results obtained here revealed that natural dyes extracted from Vitis Vinifera L. leaves can be cost-effective for dyeing wool fabrics.     

Acrylamide assisted photoinitiator-free photografting of acrylamido dyes onto wool

Upon UV irradiation wool fabrics can be photografted with photoactive acrylamido dyes at room temperature without photoinitiaors, which is eco-friendly coloration process compared with conventional adsorption-based dyeing. Acrylamide addition as a comonomer can improve the photografting probably by reducing the steric hindrance between the bulky dyes during the photocopolymerization. Even without photointiators and neutral salts, the optimal K/S values of the photografted wool reached upto 18.7 and 18.5 for Reactive Red 84 and Yellow 39 dyes respectively. The optimal UV-grafting coloration can be achieved when a UV energy of 25 J/cm² was irradiated on the padded fabrics with 6.3 %owf dye containing 0.65 mole ratio of acrylamide to the dyes. Furthermore, the color fastness of the grafted fabrics was as good as those of conventionally dyed fabrics due to the copolymerization of dyes and comonomers.     

Metal ion adsorbability of electrospun wool keratose/silk fibroin blend nanofiber mats

In this study, electrospun wool keratose (WK)/silk fibroin (SF) blend nanofiber was prepared and evaluated as a heavy metal ion adsorbent which can be used in water purification field. The WK, which was a soluble fraction of oxidized wool keratin fiber, was blended with SF in formic acid. The electrospinnability was greatly improved with an increase of SF content. The structure and properties of WK/SF blend nanofibers were investigated by SEM, FTIR, DMTA and tensile test. Among various WK/SF blend ratios, 50/50 blend nanofiber showed an excellent mechanical property. It might be due to some physical interaction between SF and WK molecules although FTIR result did not show any evidence of molecular miscibility. As a result of metal ion adsorption test, WK/SF blend nanofiber mats exhibited high Cu²⁺ adsorption capacity compared with ordinary wool sliver at pH 8.5. It might be due to large specific surface area of nanofiber mat as well as numerous functional groups of WK. Consequently, the WK/SF blend nanofiber mats can be a promising candidate as metal ion adsorption filter.     

Dimensional properties of low temperature plasma and silicone treated wool fabric

Three different silicone polymer systems, such as aminofunctional, epoxyfunctional, and hydrophilic epoxyfunctional silicone polymers, were applied onto plasma pretreated wool fabric to improve the dimensional properties. The results showed that the plasma pretreatment modified the cuticle surface of the wool fiber and increased the reactivity of wool fabric toward silicone polymers. Felting shrinkage of plasma and silicone treated wool fabric was decreased with different level depending on the applied polymer system. Fabric tear strength and hand were adversely affected by plasma treatment, but these properties were favorably restored on polymer application. Therefore, it has been concluded that the combination of plasma and silicone treatments can achieve the improved dimensional stability, and better performance properties of wool fabric. The surface smoothness appearances of treated fabrics were measured using a new evaluation system, which showed good correspondence with the results of KES-FB4 surface tester.