Union Dyeing of Easy Care-Finished Wool/Viscose and Cotton/Wool Blends

Wool/viscose (60/40) and cotton/wool (70/30) blended fabrics have been easy-care finished in the presence of certain nitrogenous additives to produce readily dyeable cationic cellulose for competitive dyeing with wool dyes. The enhancement of easy care properties and improvement in post-dyeing of the finished fabrics were determined by the nature of substrate (wool/viscose > cotton/wool), type of catalyst (ammonium persulfate > ammonium sulfate > ammonium chloride > none), the kind of nitrogenous additive, as well as the type of polyethylene glycol (PEG-400 > PEG-200 > NONE). Using triethanolamine hydrochloride as a reactive/nitrogenous additive (30 g/L) in the finishing formulation as well as curing at 150°C/3 min make it possible to attain higher fabric resiliency along with better dye receptivity, regardless of the used anionic dye. However, the change in dyeing and fastness properties of obtained dyeing is governed by the nature of the anionic dye.     

Effect of Sandospace R on the dyeability of gamma-irradiated wool,wool/polyester and polyester fabrics with some disperse dyes containing amino groups

The effect of Sandospace R on the dyeability of gamma-irradiated wool, wool/polyester and polyester fabrics towards disperse dyes has been investigated. The effects of the different factors that may affect the colour yield of the dyed samples (such as radiation dose, Sandospace R concentration, pH strength of the dye bath, dye concentration, dyeing temperature and time were studied. In general, and regardless of the studied factor, the irradiated fabric showed a significant dye affinity for the disperse dyes employed compared/to the unirradiated fabrics. However, the different fabrics irradiated to a dose of 2Mrad showed the highest colour strength with a high level of dyeing. Also, it was observed that a concentration of Sandospace R as low as 0·5% effectively enhances the dye affinity for the disperse dyes used here. Moreover, it was found that the pH of the dyeing bath at which the highest colour strength obtained was 3. Increasing the dye concentration up to 4% based on fabric weight, caused a significant enhancement in the colour strength, whilst raising/the dyeing bath temperature from 60°C to 100°C appreciably accelerated the rate of dye uptake. Complete exhaustion absorption of the disperse dye occurred over a period of 2h. © 1998 Society of Chemical Industry     

Combined Dyeing and Resin Finishing of Wool/Viscose and Cotton/Wool Blends

The objective of this study is to establish a single-stage process for anionic dyeing and easy-care finishing of wool/viscose (60/40) and cotton/wool (70/30) blended fabrics. Optimum conditions for maximizing dyeability and achieving high resiliency are: Fixapret® ECO (50 g/L), triethanolamine hydrochloride (20 g/L), ammonium persulfate (7.5 g/L) at 160°C for 3 min. The extent of improvement in both the depth of shade and easy-care properties is determined by the nature of substrate and follows the descending order wool/viscose > cotton/wool. On the other hand, the extent of dye fixation and the change in fastness properties of the obtained dyeings are determined by the class of dyestuff.     

Investigation into the dyeing of wool with Lanasol and Remazol reactive dyes in seawater

Freshwater is an increasingly scarce resource that is extensively used in textile wet‐processing. In seeking to identify alternative low freshwater‐usage coloration technology, this study examined the potential use of seawater (SEAW) as the dyeing medium for wool coloration using a range of reactive dyes. Initially, the dyeing behaviour of the wool fabric in simulated seawater (SSW) was compared with conventional dyeing from distilled water (DW) using α‐bromoacrylamide‐based Lanasol dyes and sulphatoethyl sulphone‐based Remazol dyes. These preliminary studies demonstrated that comparable coloration could be achieved in the SSW medium based on an assessment of the dye exhaustion, dye fixation, colour yield and levelness. Subsequent dyeing studies of wool using Mauritian seawater with both the Lanasol and Remazol reactive dyes confirmed that, based on the dye exhaustion, dye fixation, colour yield and levelness, comparable coloration could be achieved, highlighting the possibility of substituting freshwater with seawater as the dyeing medium.     

Dyeing properties of wool treated with liquid ammonia

Wool fibre and fabric have been treated with liquid ammonia and their surface characteristics investigated by means of SEM and ESCA techniques. The treated specimens were dyed with levelling and milling acid dyes. Although no changes in nitrogen content and fibre surface properties were detected, their dyeing rate was increased considerably as was saturation dye exhaustion. Dyeing properties were similar to those of wool treated with low-temperature plasmas by glow discharge. Fabrics treated with liquid ammonia were dyed at various temperatures in the range 30–80°C, and dye uptake was similarly increased.     

Exhaust dyeing of polyester‐based textiles using high‐temperature–alkaline conditions

The factors affecting the dyeability of polyester‐based textiles with disperse dyes in an alkaline medium were studied. It was found, for a given set of dyeing conditions, that (a) the appropriate conditions for attaining a higher color yield were 45 min at 130°C with pH 9 using a material‐to‐liquor ratio of 1/10; (b) increasing the Diaserver® AD‐95 concentration to 2% ows (based on weight of substrate) as well as including triethanolamine to 2% ows in the dyeing formulations bring about a significant improvement in the dye uptake; (c) both a preheat setting from 160 to 200°C/30 s and an alkaline weight reduction have a positive impact on postdyeing with the used disperse dye; (d) the extent of dye uptake as well as the color strength are governed by the type of substrate, that is, knitted fabric > spun yarn > woven fabric, nature of the dye stabilizer, that is, EDTA > Diaserver® AD‐95 > Tinoclorite® CBB > citric acid > none, as well as kind of the disperse dye; (e) direct reuse of the disperse dyebaths, without reconstitution, in the dyeing of the used substrates was shown to be feasible in a single shade and in the reverse‐order dyeings (dark → light); (f) one‐bath, one‐step exhaust dyeing of polyester/cotton‐knitted fabric using selected disperse reactive dyes combinations under high‐temperature alkaline conditions is feasible; and (g) the color and fastness properties of the resultant dyeings depend on the type of the used auxiliaries, in addition to the nature of disperse/reactive dyes combinations as well as compatibility with other ingredients. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3563–3573, 2003     

Neutral dyeing of wool and wool/polyester blend fabrics using sulphatoethylsulphone reactive‐disperse dyes

Two models of temporarily anionic sulphatoethylsulphone reactive disperse dyes were applied to wool, polyester and wool/polyester blend fabrics at different dyeing pH. Maximum exhaustion values and colour yield were observed at pH 7. The results showed that reactive disperse dyes containing bis‐sulphatoethylsulphone reactive groups were more convenient for neutral dyeing of wool and wool/polyester blend fabrics if compared with a dye containing a mono‐sulphatoethylsulphone group. Excellent to very good wet fastness properties on all dyed fabrics were achieved.     

Dyeing of nylon 6 fabric with a bifunctional sulphatoethylsulphone reactive disperse dye

A bifunctional reactive disperse dye containing two temporarily anionic sulphatoethylsulphone groups was synthesised and applied to nylon 6 fabric by exhaust dyeing at a variety of pH levels and temperatures. A monofunctional reactive disperse dye containing one temporarily anionic sulphatoethylsulphone group was also synthesised, and its dyeing behaviour was compared with the bifunctional dye. The bifunctional reactive disperse dye exhibited high exhaustion and total fixation yield under alkaline conditions. The results also indicate that the introduction of two temporarily anionic sulphatoethylsulphone groups of the bifunctional dye gave an enhancement in dyeing performance compared with that of the monofunctional dye. The dyes also showed very good levelling and fastness properties on nylon 6 fabric.     

Pomegranate fallen leaves as a source of natural dye for mordant-free dyeing of wool

The application of metal mordants is usually necessary in dyeing of wool with natural dyes to improve the dye exhaustion and fastness properties. The majority of metal salts generally used as mordants are considered as toxic and it is important to find replacements for them. Plant sources with high content of tannins are good candidates as bio-mordant or colourant to overcome this drawback. In this study, the waste fallen leaves of pomegranate tree were used as a source of natural dye for the eco-friendly dyeing of wool fabric without the use of metal mordants. The dyeing process variables including dye concentration, dyebath pH, and temperature were optimised using response surface methodology to obtain the highest colour strength. The colour strength was increased by increasing the natural dye powder up to 100%owf while the optimum pH and dyebath temperature were 4 and 100°C, respectively. The sample dyed under the optimal condition exhibited good fastness properties against washing and light. This study approved the potential of Punica granatum fallen leaves for the dyeing of wool without any mordant, while high fastness properties were obtained.     

One‐bath union dyeing of wool/polytrimethylene terephthalate blends†

The one‐bath dyeing of blends of polytrimethylene terephthalate (PTT) staple and wool has been investigated. The exhaustion of selected Terasil disperse dyes on PTT fibre and Lanasol reactive dyes on wool was measured as a function of temperature, together with the cross‐staining of the Terasil dyes on the wool component and the Lanasol dyes on PTT component. Most Terasil disperse dyes achieved satisfactory dye uptake on PTT at 110 °C, whereas on conventional polyester (polyethylene terephthalate) temperatures of up to 130 °C are required. An optimised union‐dyeing technique for wool/PTT blends was developed which minimised the staining of Terasil disperse dyes on wool and produced dyed goods with high levels of wet colour fastness. Carriers were not required to enhance the dyeability of PTT at low temperatures. The wool component appeared to be protected against damage at 110 °C by the reactive dyes. The results indicate the potential for blending PTT fibre and wool to produce fabrics that are easier to dye at lower temperatures than conventional wool/polyester blends.     

Eco-Friendly Sulfur Dyeing of Cellulosic Woven Fabrics

Abstract

This work demonstrated that conventional sulfur dyeing, which poses environmental problems, can be modified by using safer chemicals. The results indicate that: i) using reducing sugars as eco-friendly reductants results in an improvement in the extent of coloration; ii) the extent of improvement is determined by the reductant type; i.e., liquid glucose (LG) > thiourea dioxide (TUD) > glucose (G) > molass (M), dye/reductant ratio, as well as type of woven cellulosic fabric; i.e., viscose > cotton > linen; iii) raising the dyeing temperature to 80°C for 45 min, increasing NaCl concentration to 30 g/L, and/or minimizing the material-to-liquor ratio to 1/10 brings about an improvement in the extent of coloration; iv) efficiency of dye fixation is determined by the nature of the oxidant and follows the descending order (NH₄)₂ S₂O₈ > Na-perborate > H₂O₂ > none; and v) post-softening has positive impacts on the softness degree and washing fastness, as well as rubbing fastness properties, especially in the case of using the cationic softener, regardless of the sulfur dye used.     

Effect of atmospheric pressure helium plasma on felting and low temperature dyeing of wool

Wool fabrics were treated with atmospheric pressure helium glow discharge plasma in an attempt to improve felting and dyeing behavior with cold brand reactive dyes using cold pad‐batch method at neutral pH. On glow plasma treatment, the hydrophilicity of wool surface and its resistance toward felting was greatly improved without any significant damage to the cuticle layer. The color strength of the plasma treated dyed wool on the surface (in terms of K/S) was found to be nearly double of the color strength of dyed untreated wool fabric. However, the corresponding total dye uptake of the treated wool increased by a much lower value of 40%–50%. The reason behind this altered dyeing behavior was investigated by studying the dye kinetics using infinite bath and surface characteristics using SEM and SIMS. It was found that the glow plasma treatment greatly transformed the chemical surface of the wool fibers. It resulted in uniform removal of hydrophobic cuticular layer, which resulted in better diffusion of the dye molecules into the fiber, and formation of hydrophilic ? NH₂ groups near the surface, which helped in anchoring the dye molecules close to the surface giving higher color strength than expected. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Synthesis of acid dyes containing polyetheramine moieties and their low‐temperature dyeing properties on wool fiber

To realize the low‐temperature dyeing of wool fibers, the use of auxiliaries and wool modification are common methods. Low‐temperature auxiliaries may cause water‐pollution problems, and wool modification is a costly and uncontrollable process. In this study, new acid dyes, named D1–D3, containing polyetheramine groups were synthesized and applied to wool fiber by conventional and low‐temperature exhaust dyeing procedures. The results indicate that the new acid dyes could interact with wool‐fiber‐like auxiliaries and render a high exhaustion rate to the wool fiber at a dyeing temperature of 80 °C. In comparison with Acid Blue 25, the D1–D3 dyes showed an increased dyeing rate, especially under a dyeing temperature of 80 °C. Despite the bigger relative molecular masses of D1–D3, the exhaustion rates of D1–D3 were still higher, and the times of half‐dyeing were shorter than that of Acid Blue 25. The color differences between the wool fabrics dyed with the four dyes at 80 and 98 °C, respectively, were compared. We found that the color differences of D1–D3 between 80 and 98 °C were smaller than that of Acid Blue 25. The interactions between the dyes and wool fiber were analyzed and manifested by the measurement of the ζ potential of the dyes and wool fiber. The leveling and transfer properties of the D1–D3 dyes were also investigated, and the color differences of the wool fabrics dyed with Acid Blue 25, D1, and D2 were very low at all measured pH values and temperatures. The fastnesses of D1–D3 on wool fabric were almost the same as that of Acid Blue 25. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45793.     

Dyeing of wool with temporarily solubilised disperse dyes

Temporarily solubilised disperse dyes derived from aminophenyl-4-(β-sulphatoethylsulphone) have been applied to wool fabric without the use of a levelling agent. By virtue of their characteristic dye structure, excellent levelling properties were observed on wool fabric. Good exhaustion, fixation and fastness test values were also obtained.     

Reactive dyeing systems for wool fibres based on hetero-bifunctional reactive dyes. Part 1: Application of commercial reactive dyes

The wool dyeing properties, such as exhaustion and fixation parameters, of selected hetero-bifunctional Sumifix Supra dyes and some other commercial reactive dyes were quantified under various dyebath pH conditions. Studies of the dyeing of wool serge fabric indicated that Sumifix Supra dyes could produce reasonably high fixation values. However, remarkably improved fixation values were obtained when these dyes were pre-activated to the vinylsulphone form and dyed in this form, especially at low pH values (pH 4 or lower).     

Adsorption of different dyes from aqueous solution using Si-MCM-41 having very high surface area

Adsorption characteristics of four different dyes Safranin O (cationic), Neutral Red (neutral), Congo Red (anionic) and Reactive Red 2 (anionic) on Si-MCM-41 material having very high surface area are reported. The surface morphology of Si-MCM-41 material before and after adsorbing dye molecules are characterised by FTIR, HRXRD, nitrogen adsorption–desorption isotherms, FESEM, and HRTEM. The adsorption capacities of Si-MCM-41 for the dyes followed a decreasing order of NR > SF > CR > RR2. The adsorption kinetics, isotherm and thermodynamic parameters are investigated in detail for these dyes using calcined Si-MCM-41. The kinetics and isotherm data showed that both SF and NR adsorb more rapidly than CR and RR2, in accordance with pseudo-second-order kinetics model as well as intraparticle diffusion kinetics model and Langmuir adsorption isotherm model respectively. The thermodynamic data suggest that the dye uptake process is spontaneous. The high adsorption capacities of dyes on Si-MCM-41 (q_m = 275.5 mg g^?1 for SF, q_m = 288.2 mg g^?1 for NR) is explained on the basis of electrostatic interactions as well as H-bonding interactions between adsorbent and adsorbate molecules. Good regeneration capacity is another important aspect of the material that makes it potent for the uptake of dyes from aqueous solution.     

Dispersant‐free dyeing of poly(lactic acid) fabric with temporarily solubilised disperse dyes from azopyridone derivatives

Poly(lactic acid) fibre is derived from annually renewable crops and known to be 100% compostable. In order to extend its environmental friendliness into the dyeing process, dispersant‐free dyeing of poly(lactic acid) fabric with three temporarily solubilised azo disperse dyes based on hydroxypyridone moiety containing a β‐sulphatoethylsulphonyl group was investigated. The dyes were successfully applied to poly(lactic acid) fabric without the use of dispersants. The colour yields of the dyes on poly(lactic acid) fabric were observed to be dependent on dyebath pH and dyeing temperature. The optimum results were obtained at pH 4–5 and 110 °C. One of the dyes showed a colour yield as good as that of a commercial disperse dye and good build‐up on poly(lactic acid) fabric. All of the dyes could be alkali cleared owing to ionisation of the dye under mild alkaline conditions. Wash fastness was good to very good, and light fastness was good. The chemical oxygen demand levels of the poly(lactic acid) dyeing effluent from the dyes were considerably lower than those from a commercial disperse dye.     

UV-Protective Finishing of Cellulose/Wool Blended Fabrics

There is a growing need and special attention for using textile products to provide effective protection against such damage of UV-radiation, i.e., skin cancer, sun burn, and photo-aging, in the recent years. In this research work a new approach for upgrading the UV-protective properties of cotton/wool and viscose/wool blended fabrics for high quality/trans seasonal apparel, was investigated. Factors affecting the UVB-protection function of the aforementioned substrates such as type and concentration of finishing additives, as well as subsequent treatment with cu-acetate or dyeing with anionic or cationic dyes were studied. The experimental data show that: i) the enhancement in the UV-protection factor (UPF) of the finished fabrics is determined by the type of finishing additives, i.e., citric acid ≥ aspartic acid ≥ tartaric acid ≥ none, chitosan TEA.HCL ≥ choline chloride ≥ none, β-cyclodextrin CMC-30 PEG-600 > none, and Siligen® WW > W Siligen® PEP ≥ Leomin® NI-ET ≥ none, regardless of the used substrate, ii) UPF values are governed by the type of substrate, i.e., viscose/wool ≥ cotton/wool, irrespective of the used additives, iii) post-treatment with cu-acetate or post-dyeing with the used dyestuffs brings about a dramatic improvement in UPF values, and iv) UPF values are determined by the finishing regime and follow the descending order:

Resin finishing → post dyeing > resin finishing → posttreatment with Cu-acetate > resin finishing in presence of additives > resin finishing in absence of additives.     

Differential dyeing of wool fabric with metal‐complex dyes after ultraviolet irradiation

Experiments were conducted to investigate the ultraviolet irradiation of wool fabric as a pretreatment for differential dyeing. Wool fabric was irradiated using a medium‐pressure mercury lamp in order to obtain, on the irradiated area, increased dye uptake under the same dyeing conditions as untreated wool. The chemical modification of the fibre surface as a result of ultraviolet irradiation was confirmed by an increase in metal ion absorption and hydrophilicity, in agreement with Fourier Transform‐infrared–attenuated total reflectance spectra, although scanning electron microscopy showed that the fibre morphology was unaffected. A selection of 1:1 metal‐complex dyes was used to show the maximum colour difference between irradiated and untreated areas of the fabric. The experiments focused on two effects: a double face with the same shade but different depths (greater depth on the treated side), and a double face with different shades. The latter effect was achieved by dyeing the irradiated fabrics with mixtures of acid and metal‐complex dyes. Rubbing and washing fastness evaluations at 50 °C confirmed that the dyeings after irradiation with the selected 1:1 metal‐complex dyes scored identically to conventional dyeings.     

Dyeing properties of oxygen low-temperature plasma-treated wool and nylon 6 fibres with acid and basic dyes

Wool and nylon 6 fibres treated with oxygen low-temperature plasma were dyed with acid and basic dyes. Despite the increase of electronegativity of the fibre surface caused by the plasma treatment, the rate of dyeing of wool was increased with both dyes, while that of nylon 6 was decreased with the acid dye and increased with the basic dye.