Isolation, identification and dyeing studies of betanin on modified acrylic fabrics

Mature red fruits of Opuntia ficus-indica contain two soluble pigment, betanin and indicaxanthin. The optimal conditions for dye extraction were to mix 50 g of juice from cactus pears with 100 mL of acidified water as solvent for dye extraction. Two main dyes were purified from the pigment extract by chromatography and identified by UV-vis, HPLC and LC-MS techniques as indicaxanthin (15 mg per 100 g) and betanin (280 mg per 100 g). The effect of dye bath pH, salt concentration, dyeing time and temperature was studied. The optimal conditions for dyeing modified acrylic fabrics with betanin dye were carried out at 50 °C for 45 min at pH 5. Un-mordanted samples have good properties of water and washing fastness. Mordant CoSO₄ was found to give good light fastness (rating 5).     

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.     

Extraction,Dyeing, and Antibacterial Properties of <Emphasis Type="Italic">Crataegus Elbursensis</Emphasis> Fruit Natural Dye on Wool Yarn

Fruits obtained from shrubs of the Crataegus elbursensis (C. elbursensis) plant demonstrate significant antioxidant and antibacterial properties. In this study, natural dye was sono-extracted from fresh and dried fruits and applied in dyeing and antibacterial finishing of wool. The maximum sono-extraction yield was obtained when optimal conditions of ethanol/ water (4/1 v/v) as extracting solvent, time 30 min, pH 4, temperature 50 oC, and C. elbursensis concentration 10 g/l were used. When wool yarns were dyed with the extracted natural dye, the maximum dye uptake was achieved using dye concentration 75 % owf, and dyeing condition of 100 oC, 60 min, pH 4, and LR 100:1. Different metal salts like aluminum sulfate, copper sulfate, and tin chloride were applied on wool by pre-mordanting method and their effects on dye uptake, color variation, and color fastness were examined. Results showed that the natural dye itself had relatively high uptake and good color fastness on un-mordanted wool. Further, each mordant had different effect on dye uptake, color variation, and color fastness properties depending on its coordination ability with dye molecules and wool chains. Moreover, dyed yarns showed good antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacteria.     

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.     

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.     

Dyeing properties and colour fastness of cotton and silk fabrics dyed with<Emphasis Type="Italic">Cassia tora L.</Emphasis> extract

A natural colorant was extracted fromCassia tora L. using buffer solutions (pH: 2–11) as extractants. The dyeing solution (Cassia tora L. extract) extracted using pH 9 buffer solution was found to give the highest K/S values of dyed fabrics. Cotton and silk fabrics were dyed withCassia tora L. extract at 60°C for 60 min with pre-treatment of various metal salts as mordants. It was found thatCassia tora L. extract was polygenetic dyestuffs and its major components were anthraquinones. Studies have been made on the effects of the kind of mordant on dyeing properties and colour fastnesses of cotton and silk fabrics. The K/S of cotton fabrics increased in the order of the dyeing using FeSO₄>CuSO₄>ZnSO₄>MnSO₄≅Al₂(SO₄)₃>NiSO₄>none, however, the K/S of silk fabrics increased in the order of the dyeing using FeSO₄>CuSO₄>ZnSO₄≅Al₂(SO₄)₃>MnSO₄≅NiSO₄>none. It was found that the K/S values of dyed fabrics were largely affected by the colour difference (ΔE) between mordanted fabric and control fabric. However, they were not depended on the content of mordanted metal ion of the fabrics. Mordants FeSO₄ and CuSO₄ for cotton fabric, FeSO₄, CuSO₄, and Al₂(SO₄)₃ for silk fabric were found to give good light fastness (rating 4).     

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.     

Dyeing of synthetic fabrics in water using azoic dyes based on boronic acid derivatives

Development of water-soluble dyes for the dyeing of different textile fabrics is essential for the textile industry due to ecological and economical reasons. In this study, a series of new azoic dyes were prepared by diazotization reaction between the phenyl boronic acid and different aniline derivatives, and their dyeing capacity in aqueous solution was evaluated. The synthesized boronic azo dyes present good water solubility and can dye polyamide (nylon), wool, silk, and cellulose acetate fabrics. The effect of factors such as concentration of dye, dyeing temperature, and pH on the level of color strength (K/S) was studied. The dyeing results showed that higher color strength K/S (about 16) and fastness properties (about 4/5) with boronic acid dyes were achieved at higher temperatures avoiding the use of surface agents, mordants, and other polluting chemical additives.     

Properties of basic dyes on polyacrylonitrile treated m-aramid fabrics

Treatment of polyacrylonitrile (PAN) onto m-aramid fabric was carried out by pad-dry-cure method using dimethylformamide (DMF) dissolved acrylic fiber solution. The obtained PAN treated m-aramid fabric was dyed using exhaustion method with basic dyes. The effect of PAN treatment on fabric stiffness property was acceptable with acrylic fiber solutions ranging from 1 wt% to 4 wt%. Whilst, more than 4 wt% PAN treated fabrics exhibited undesirable stiffness. The dyeing results showed that PAN treated m-aramid fabrics exhibited a significant increase in color strength when compared to untreated fabric, arising from an increase in anionic dye sites (styrene SO₃ ^? group). Wash fastness was comparable to that of untreated fabric, indicating the strong interaction between dye molecules and the PAN. Rubbing fastness of treated fabrics was not affected by treatments with PAN concentrations lower than 4 wt%. Further increase in PAN concentration led to poorer rubbing fastness property due to the problem of surface dyeing. For light fastness, the PAN treatment failed to improve the light fastness property which is the main disadvantage of basic dyeing of aramid fabric. Finally, in case of PAN treatments with the range of 1 wt% to 4 wt%, the flame retardancy property of PAN treated m-aramid fabrics was found not affected by the percent add-on. However, above 4 wt% PAN treatment, the flame retardancy performance became deteriorated.     

A new method for brightening wool in a dye bath

A new method for brightening wool during dyeing has been developed using tert-butylamine borane in the dyebath. The method was found to be significantly superior to current industrial practice using hydroxylammonium sulphate or its derivatives. The effects of tert-butylamine borane on dye shades and dyeing quality have also been assessed with a range of commercial wool dyes. The results of this study have shown that the new method is effective in preventing hydrothermal wool yellowing during dyeing, and can produce brighter shades of dyeings without significantly altering the dye shades or impairing the dyeing fastness and mechanical properties of the dyed wool under the conditions examined. The advantages of the concurrent bleaching and dyeing method over conventional bleaching and dyeing processes include reduced processing time, improved energy efficiency, and lower water consumption, arising from reduction in the number of fiber treatment steps.     

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.     

Sonicator dyeing of natural polymers with <Emphasis Type="Italic">Symplocos spicata</Emphasis> by metal chelation

Symplocos spicata (local name: Dom sheng) belonging to Family Symplococeae produces yellowish brown natural dye which has been used for dyeing textiles since ancient times by the Monpas tribe of Arunachal Pradesh. Symplocos spicata (Dom Sheng) was found in the Lumla area of Tawang district. Leaves of the plant are used by the Monpas and Tibetans for extraction of dye. Innovative sonicator dyeing with S. spicata showed that pretreatment with 2–4% metal mordant of the weight of the fabric is optimum showing very good fastness properties for dyed natural polymers such as cotton, wool, and silk. CIELab and K/S of the dyed fabrics were also evaluated. The superiority of sonicator dyeing over conventional dyeing has been established through this study.     

Natural dyeing of cotton with <Emphasis Type="Italic">Xylocarpus granatum</Emphasis> bark extract: Dyeing,fastness, and ultraviolet protection properties

In this research we investigated the dyeing of cotton fabrics with extracts of Xylocarpus granatum, a mangrove plant with a long history of use in leather tanning and textile dyeing. X. granatum bark was extracted and spray-dried, yielding a tannin-rich, reddish-brown powder. This powder proved a suitable colorant for the natural dyeing of cotton with promising color fastness properties to wet treatments (washing, water, sea water, and perspiration), hot pressing, crocking, and light exposure. However, the dye alone produced only weak levels of coloration and therefore metallic salt mordants were employed to improve the color strength, through the formation of insoluble tannate complexes. The resulting fabric K/S values were dependent on the mordant used and exhibited the following trend: ferric sulfate > sodium dichromate > copper sulfate > potassium aluminum sulfate > no mordant, for fabrics exposed to mordants before and after dyeing. Mordanting resulted in slight variations in shade and color fastness. In most cases, the color fastness properties were preserved, except for color fastness to light and hot pressing, for which lowered ratings were found for some mordants. Stiffness and mechanical performance were not greatly affected by dyeing or mordanting, except for sodium dichromate mordanting which significantly stiffened and weakened the fabric. The ultraviolet protection factor (UPF) of all the dyed samples achieved the maximum (50+) level, highlighting the excellent UV shielding properties of the fabric. Overall, X. granatum bark extract is a promising, effective colorant for the natural dyeing of cotton in terms of appearance, fastness, and physical characteristics.     

<Emphasis Type="Italic">Limoniastrum monopetalum</Emphasis> stems as a new source of natural colorant for dyeing wool fabrics

In the present study, an attempt has been made to dye the wool fabric with Limoniastrum monopetalum stems, as a source of natural dye, which has not been exploited so far. Optimization of extraction parameters was done. Optimum results of extraction process were obtained with a dye concentration of 60 g/l, a temperature of 90 °C during 100 min. The study of different factors effecting dyeability of wool fabrics by aqueous L. monopetalum stems extract showed that the pH of dye bath and dyeing temperature and time affected considerably the color yield. The best results were obtained at the following conditions; pH 2, 100 °C, and 60 min. Metal mordants, when used in conjunction with L. monopetalum dye, allowed to obtain various shades. The determination of phenolic contents of aqueous L. monopetalum stems extract showed a high amount of phenolic components. Based on RP-HPLC, the coloring extract of L. monopetalum stems contains tannins and polyphenols. The major identified phenolic compounds were procatechuic, Trans-cinnamic and gallic acids. Hence, aqueous L. monopetalum stems extract could be successfully exploited for dyeing wool fabrics with high color yield (K/S).     

Statistical optimization of wool dyeing with Alizarin Red S as a natural dye via central composite design

Recently a revival interest in the use of natural dyes in textile coloration has been growing. The major parts of natural dyes are anthraquinones. Depending on substituents, anthraquinone compounds are dyes, as represented by Alizarin Red S (ARS) which is a major constituent of the natural colorant madder. In this study, colorization of wool fiber by ARS as a natural dye was studied. The progress of the colorization process was followed spectrophotometrically at 500 nm as λ _max. The effective factors on the process were investigated using one factor at a time (OFT) method. Then, the central composite design (CCD) method was applied to design experiments for the evaluation of the interactive effects of the four most important operating variables. The values of the optimized factors for OFT and CCD methods in wool dyeing with ARS were respectively as follow: temperature 70 °C and 55 °C, L/R: 40/1 and 40/2, pH 5.0 and 2.5 and time 60.0 min and 42.0 min. The predicted results by CCD had significantly higher exhaustion percentages and relatively better fastness properties than OFT and were found to be in a good agreement (R²=0.9908) with those obtained by performing experiments. Finally, the obtained results were shown a good wash fastness for dyed wool with ARS.     

Comprehensive utilization of the hydrolyzed productions from rice hull

The study based on pretreatment, hydrolyzation and separation processes with the raw material rice hull, provides a comprehensive utilization of the hydrolyzed productions, such as glucose (C₆H₁₂O₆) from cellulose, silica (SiO₂), and byproduct crystalline sodium sulfate (Na₂SO₄·10H₂O). The optimum hydrolysis conditions are as follows: the concentration of H₂SO₄ is 72% (wt.%), the temperature is 50 °C, the ratio of H₂SO₄ solution volume (mL) to the rice hull mass (g) is 10:1 and the time is 5 min, the glucose yield rate reaches 45.6% (wt.%). The concentration of glucose solution could be 0.1 g/mL after neutralization measured by ultraviolet spectrophotometer (UV-VIS). Silica powder was below 50 nm characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The main byproduct crystalline sodium sulfate was featured by XRD and photographs.     

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.     

Synthesis, characterization and application of quinazolinone based reactive dyes for various fibers

Seven hot brand heterocyclic mono azo reactive dyes (7a–g) have been synthesized by coupling diazotized 2-phenyl-3{4′-[(4″-aminophenyl)sulphonyl]phenyl}-quinazoline-4(3H)-one-6-sulphonic acid (4) with various 2-chloro-4-nitro anilino cyanurated coupling components (6a–g) and their dyeing performance on silk, wool, and cotton has been assessed. The purity of dyes was checked by thin layer chromatography. These dyes were identified by recording IR and ¹H-NMR spectra. The λ _max, R _f value, %exhaustion, %fixation, light fastness, wash fastness, rubbing fastness, reflectance (%R) value, and K/S value have also been studied.     

Meta-mordant Dyeing with <Emphasis Type="Italic">Camellia sinensis</Emphasis> (L.) O. Ktze var. <Emphasis Type="Italic">waldensae</Emphasis> (S.Y.Hu) Chang (Yellow-bud Tea) Extract for Wool Fabrics Treated by UV Radiation

The wool fabrics were treated by ultraviolet (UV) radiation and then dyed with Camellia sinensis (L.) O. Ktze var. waldensae (S.Y.Hu) Chang (yellow-bud tea) extract using meta-mordant dyeing method. The results indicated that the hydrophilicity of wool fabrics was improved after UV radiation treatment, which was conducive in improving color performance for the meta-mordant dyeing with yellow-bud tea extract of wool fabrics. The optimal dyeing process was that the powdered extract (5.0 % o.w.f) and the CuSO₄ (2.0 % o.w.f) were added to the dyeing liquor, the pH value was adjusted to 3.5-4.0 by HCOOH, the wool fabrics treated by UV radiation for 10 min and then were dyed at a bath ratio of 1:50 under 95 °C for 70 min. By means of three-factor quadratic current rotation revolving design (TQCRRD) method, the computation results of the mathematical equations and models indicated that UV radiation was the most important factor for meta-CuSO₄ dyeing with yellow-bud tea extract for wool fabrics.     

Sensitivity of Ascochyta rabiei populations to prothioconazole and thiabendazole

Ascochyta rabiei causes Ascochyta blight, a yield-limiting disease of chickpea (Cicer arietinum) world-wide. In 2007, fungal populations of A. rabiei resistant to the QoI group of fungicides were detected in the Northern Great Plains of the United States. Assays were conducted to determine fungal sensitivity for two alternative fungicidal modes of action. A total of 78 isolates of A. rabiei collected between 1983 and 2007 were screened to determine baseline sensitivity to the demethylation-inhibiting foliar fungicide, prothioconazole, and 100 isolates collected between 1987 and 2007 were screened for sensitivity to the methyl benzimidazole carbamate (MBC) fungicide, thiabendazole. Isolates were tested using an in vitro mycelial growth assay to determine the effective fungicide concentration at which 50% of fungal growth was inhibited (EC₅₀) for each isolate-fungicide combination. Baseline EC₅₀ values of prothioconazole ranged from 0.0526 to 0.2958 μg/ml, with a mean of 0.1783 μg/ml. Isolates of A. rabiei collected from 2007 to 2009 from North Dakota chickpea fields exposed to prothioconazole, were screened for prothioconazole sensitivity using the same assay. Mean EC₅₀ values for these isolates were 0.3544 μg/ml, 0.3746 μg/ml, and 0.7820 μg/ml, respectively. These values represent an approximate 2.0 (2007-2008) and 4.4-fold (2009) decrease in sensitivity from the baseline mean. EC₅₀ values of thiabendazole ranged from 1.192 to 3.819 μg/ml, with a mean of 2.459 μg/ml. No significant decrease in fungicide sensitivity was observed for thiabendazole. To date, no loss of Ascochyta blight control has been observed with the use of either prothioconazole or thiabendazole.