Dyebath Exhaustion Research Articles

The Synthesis and Application of Reactive Dyes Based on 4,4'-methylene bis-m-nitro aniline on Various Fibres

Hot brand bisazo reactive dyes (D1 to D10) have been synthesized by coupling tetrazotised 4,4’-methylene bis-m-nitro aniline with various cyanurated coupling components. They were applied on silk, wool and cotton fibres. Their dyeing performance on silk, wool and cotton has been assessed. The purity of dyes was checked by thin layer chromatography. The IR spectra showed all characteristic band and PMR spectra of representative dye showed all the signals. The percentage dye bath exhaustion on different fibres was reasonably good and acceptable. The dyed fibres showed moderate to very good fastness to light, washing and rubbing.

A novel application of synthesised based squarylium dyes on nylon 6, and silk woven fabrics

Abstract Squarylium dyes were synthesized and characterized by different spectrometric techniques using FT-IR, UV-visible and GC–MS, the dyes gave molar extinction coefficient values greater than 5.2812 × 105 L mol−1 cm−1. Their fastness properties in respect to wash, light, perspiration and hot pressing on nylon 6, and silk fabrics were analyzed, effects of time, temperature, carrier concentration and pH was also investigated and reported. The dyed fabrics showed good to very good wash, light fastness, and perspiration good to very good hot pressing on nylon 6 and good to very good on silk fabric, respectively. The dye-bath exhaustion was found to be between 76 and 92% on nylon 6 and 57 and 85% on silk, respectively. The percentage exhaustion on nylon 6 was found to be very good to excellent but on silk it was found to be good to very good. These studies showed that squarylium dyes can be applied to nylon 6 and silk fabrics, but better performance was found on nylon 6 than silk fabric.

Investigation of Mordant Application in Reactive Dyeing of Nylon Fabrics

Nylon fibers were the first synthetic fibers to be produced on an industrial scale, and they are one of the most consumed synthetic fibers due to their visual and usage properties. Reactive dyes have been commercially produced since the mid-20th century, and they are mostly preferred in dyeing cellulosic fibers. The most important property of reactive dyes is their ability to make covalent bonds within the fiber. Mordants are used mainly in the application of natural dyes to hold and retain the dye molecules in the fiber. In this paper, nylon fabrics were dyed with three reactive dyes having different reactive groups (monochlorotiazine, trifluoropyrimidine and monochlorotriazine/vinylsulfone) in the presence of three chemical mordants (iron (II) sulfate, potassium aluminum sulfate and tannic acid) to obtain better exhaustion and coloration properties. Pre-mordanting, meta-mordanting, and post-mordanting processes were used for dyeing. The dyeings were performed at two dyeing concentrations (0.5% and 2% owf), and at three pH levels (pH 2, 4, and 6). The percentage of dyebath exhaustion (%E), the percentage fixation of the dye which exhausted (%F) and the overall percentage fixation (%T) were calculated after pyridine extraction. Wash and light fastness tests were applied on the dyed samples. The results were discussed via % E, % T and CIELAB color differences (Δ Eab*). The results revealed that mordant usage improved the coloration properties of reactive dyes on nylon fabrics. The % E and % T results changed according to the independent variations of pH level, mordant chemical and mordanting method. The correct pH level and mordanting method gave the best dyeing and fastness results for the dyes under test.

Major Development in Cotton Coloration: A Review

Most cotton fabrics are dyed with reactive dyes because they produce a full range of bright fashion colours with a high degree of wash fastness.Reactive dyes are frequently considered as king of dyes for cotton owing to their simple application techniques. However, reactive dyes are anionic and cotton fibers gain anionic surface charge in water, the charge repulsion adversely affects the dye bath exhaustion. Large quantity of electrolyte is added to overcome this problem. Some problems such as low dye utilization, high degree of salt utilization and colored effluent due to unexhausted, unfixed, and hydrolyzed dyestuffs, and high volume of waste water discharged, always exist in the application of reactive dyes.These electrolytes are neither exhausted nor destroyed and hence remain in the discharge dye liquor which leads to enormous environmental problem. Due to these problems this class of dyes is the most unfavorable one from the ecological point of view, these effluents produced gives high values of BOD/COD and increases salinity of the rivers affects the delicate biochemistry of aquatic life.A number of more environmentally sustainable approaches for reactive dyeing of cotton have been proposed to overcome the polluted effluent problem. This paper reviews options to improve the sustainability of the colouration process through development in dye structure, modification of dyeing machinery and processes, chemical modification of cotton fibre prior to dyeing, and use of organic compounds in place of inorganic chemicals.

Insights into Cotton Dyeing Using Limoniastrum Monopetalum Leaves Aqueous Extract: Extraction and Dyeing Processes Optimization

ABSTRACT A great deal of attention was addressed to the development of natural dyes that are safe, non-allergic, nontoxic, and environmentally friendly. In this investigation, Limoniastrum monopetalum leaves were studied as a source of ecological dye for cotton fabric dyeing. FT-IR spectroscopy indicated that the studied leaves were rich of hydroxyl and carbonyl groups suggesting the presence of phenolic and flavonoid structures. The extraction procedure was performed under different operating conditions; extraction time (5–90 min), temperature (30–120°C), pH (2–11) and aqueous extract concentration (10–90 g/L). Response Surface Methodology (RSM), with the assistance of Minitab17.1.0, was used to estimate the interaction between experimental factors. The optimum conditions for the extraction procedure were; time = 15 min, temperature = 40°C, pH = 9, and dye concentration = 80 g/L. Influences of the main dyeing conditions on the color strength (K/S) and the dye bath exhaustion [E (%)] were also discussed. The optimal values for dyeing were: pH of dyeing bath = 8.9, temperature = 100°C and dyeing duration = 43 min. The fastness properties of colored cotton samples were found to be improved using alum, chitosan, and pomegranate peel as mordants.

Synthesis, application and colorimetric study of some monoazo reactive dyes

A new series of monoazo reactive dyes (6a-6l) based on 1,3,5-trichloro-s-triazine and 4-(ethylsulfurate sulfonyl)aniline reactive groups were synthesized by reacting diazotised 3-(4-(4-amino-3-bromo benzyl)-2-phenyl quinazoline-4(3H)-one with various 4-β-sulphatoethylsulphonylphenyl-1-amino cyanurated coupling components. The chemical structure of synthesised dyes were confirmed by nitrogen elemental analysis, Infrared and PMR spectra. These dyes have been applied out on silk, wool and cotton fibres. They were exhibit variety of colour shades with very good depth and informality on the fibres. The percentage dye bath exhaustion and fixation on the said fibre were found to be very good. The dyed fibres indicated good to excellent wash fastness, fair to very good light fastness and good to excellent rubbing fastness properties. Colour difference data and K/S value were also carried out.

Synthesis of fluorescent cationic coumarin dyes with rigid molecular structures to improve lightfastness and their related modacrylic dyed fibers

In this study, three novel cationic, fluorescent, coumarin dyes (6a, 6b and 6c) with rigid molecular structures were synthesized and characterized by spectroscopic studies. The photochemical behavior (UV light) of these dyes was studied in ethanol and DMF solvents. Compared to that of a commercial dye (basic yellow-40), the synthesized dyes exhibited good photostability in these solvents. A dyeing experiment was performed on modacrylic fibers with these dyes using a traditional cationic dyeing process. The effect of pH on the absorption spectra and dye bath exhaustion were also studied. The dyeing results showed that all the dyes exhibited obvious fluorescence effects. Based on the luminance factor (β), and photostability behavior, the synthesized dyes can hopefully be applied in high-visibility, fluorescent, yellow warning textiles with improved lightfastness.

Ecological and cleaner process for dyeing bicomponent polyester filaments (PET/PTT) using ecological carriers: analysis of dyeing performance.

Thanks to their excellent properties, bicomponent filaments, in particular, polyethylene terephthalate (PET)/polytrimethylene terephthalate (PTT) are more and more used in stretchable clothing. Despite the researchers' efforts, the dyeing of these filaments still presents several problems which should be resolved. Manufacturers must choose between dyeing polyester under pressure at high temperatures (close to 130 °C) to have less toxic and cheaper textile effluents and/or dyeing at low temperatures (not exceeding 100 °C) which needs the use of toxic carriers. This paper presents a new opportunity and the feasibility of dyeing bicomponent polyester filaments using an economic and clean process at a temperature equal to 100 °C and by replacing toxic carriers by ecological ones. Three kinds of ecological carriers, namely o-Vanillin, p-Vanillin and Coumarin, are used to improve the dyeing performance of bicomponent filaments with three disperse dyes having different molecular weights. They were compared to three conventional ones largely used in industry. The effect of each carrier on dyeing performance (dye bath exhaustion, color strength and CIELab coordinates) was then investigated. The obtained results prove that ecofriendly carriers constitute a good solution to replace the toxic ones and allow to obtain the same, or even better dyeing performance and fastness properties.

Studies on dyeing properties of chitosan modified cellulosic fiber

This paper presents the possibility of salt free dyeing of cotton fabric with reactive dye by treating the cotton with chitosan from fish scale and used as a salt for dyeing of cotton with reactive dye. Cellulosic fiber acquires negative charge in aqueous medium and thus repels negatively charged dye anion during dyeing. Such repulsion between fibre and dye is offset by using large quantity of salt in dye bath, particularly for reactive dyes. A low dye bath exhaustion also leads to low dye fixation of reactive dyes on cotton. Therefore the discharged wastewater from dye house creates avoidable environmental threats due to very high dye concentration. Hence, surface modification of cotton to increase dye-fibre interaction is thus the best route to overcome the lack of affinity of cotton to reactive dyes making salt-free reactive dyeing. In this investigation an attempt was made to modify cotton with chitosan extracted from fish scales. The chitosan modified cotton was dyed with reactive dye and compared with the conventional dyed cotton. The color strength of the modified cotton fabric was better than that of conventional sample which is 18.88 and 18.02 respectively. Better fastness properties were experienced in treated cotton sample than the ordinary sample. The fastness properties obtained were better than the conventional sample. From this investigation it was revealed that surface modification of cotton by treatment with chitosan provided better dyeing properties and it can be the best possibility for salt free dyeing of cotton.

A systematic study of dyeing polybutylene succinate fibres

AbstractBiodegradable polybutylene succinate (PBS) fibre is a new type of textile fibre, but its application in the textile industry is limited by the lack of related dyeing methods. In this study, the solubility parameters of PBS fibres are calculated, and solvent dyes with similar solubility parameters are proposed to dye PBS fibres to show that the dyeing scheme creatively resolves the difficulty in dyeing PBS fibres. The technical parameters of suitable dyes, and the dyeing conditions with ethanol as the dyeing medium, consisted of a dyeing temperature of 90°C, a dyeing time of 30 minutes and a liquor ratio of 30:1. The dyeing results show that the levelling property is good, the dyebath exhaustion is high, and the washing fastness, the rubbing fastness and the perspiration fastness index of the dyed fibres are satisfactory.

Dyeing of Meta-Aramid Fibres Previously Functionalized with Poly(Diallyldimethylammonium Chloride)

In this work, a weft-knitted fabric produced from 100% meta-aramid (MA) fibre was functionalized by using polyelectrolyte, Poly (diallyldimethylammonium chloride) (PDDA), in order to modify its surface for dyeing with an uncommon dye class for MA fibres. Contact angle, dye solution drop adsorption, Scanning Electron Microscopy (SEM), reflectance spectrophotometry, washing and rubbing fastness tests were performed to study the effects caused by the interaction between PDDA and MA fabric. Good results of dyebath exhaustion with excellent values of colour strength were obtained for the samples previously treated with PDDA. These results showed the possibility of obtaining distinct and deep colours besides generating a lower energetic cost using shorter time and lower dyeing temperature as compared to those normally used in the MA dyeing process.

Synthesis and Structural-reactivity Studies of Bifunctional MCT/SES (Monochlorotriazine/ Sulphatoethylsulphone) Azo Reactive Disperse Dyes Applied to Wool and Polyester Fabric

Reactive disperse dyes containing monochlorotriazine/sulphatoethylsulphone reactive moieties were synthesized by condensing aniline with cyanuric chloride and further reacting it with a series of monoazo dyes obtained by diazotising 1-aminobenzene-4-β-sulphatoethylsulphone and coupling with various substituted 2-amino-4-phenylthiazole derivatives. The dyeing performance of the dyes was evaluated on polyester and wool fabrics. The dyes obtained gave various shades ranging from reddish to bright red colours. They had good depth and good levelling properties. They dyed fabrics showed moderate to good light fastness properties and very good to excellent fastness to washing and perspiration. The dye bath exhaustion on the polyester and wool fabrics were found to be very good and their fixation values were moderate.

Influence of dielectric barrier discharge treatment on mechanical and dyeing properties of wool

Physical and chemical properties of wool surface significantly affect the absorbency, rate of dye bath exhaustion and fixation of the industrial dyes. Hence, surface modification is a necessary operation prior to coloration process in wool wet processing industries. Plasma treatment is an effective alternative for physiochemical modification of wool surface. However, optimum processing parameters to get the expected modification are still under investigation, hence this technology is still under development in the wool wet processing industries. Therefore, in this paper, treatment parameters with the help of simple dielectric barrier discharge plasma reactor and air as a plasma gas, which could be a promising combination for treatment of wool substrate at industrial scale were schematically studied, and their influence on the water absorbency, mechanical, and dyeing properties of twill woven wool fabric samples are reported. It is expected that the results will assist to the wool coloration industries to improve the dyeing processes.

Cationization of Cotton Using Extracted Keratin from Ethiopian Sheep Wool Waste for Salt Free Dyeing with Reactive Dye

Conventionally, dyeing of cotton with reactive dye can be done in the presence of salt to improve exhaustion by reduction the repletion forces in between the anionic dye and hydroxyl functional groups of cotton. But after dyeing salt and hydrolysed reactive dye effluent becomes directly disposed to the environment and critically affect human health and biodiversity live inside water bodies. To eliminate salt consumption and enhance wool waste utilization, the present study focused on an eco-friendly approach of salt free dyeing of cotton with reactive through cationization using extracted keratin hydrolysed from Ethiopian sheep wool waste. Keratin protein was successfully extracted from wool waste using different combinations of NaOH Concentration, Temperature, pH and Time. The optimum extraction parameters were selected by investigating the maximum absorption obtained at λ max under UV/Vis Spectrophotometer. The dyeing efficiency of keratin treated cotton was compared with untreated cotton. The dye bath exhaustion percentage for cationized by pad-dry, pad –dry-cur and untreated cotton fabric was evaluated using UV/Vis spectrophotometer and recorded as 70 %, 63.3% and 56.6% respectively. The chemical composition of the cationized fabric was investigated under FTIR. The color strength (K/S), CIE L*a*b* was examined under Color eye - 300 spectrophotometer and the cationized fabric shows better K/S value as compared with untreated fabric. The color fastness for both cationized and untreated dyed fabrics also evaluated and investigated using international standards. The cationized cotton fabric shows very good-excellent color fastness property which is better than that of untreated fabric.

Effect of chelating agent in disperse dye dyeing on polyester fabric

In this study, mild acid based chelating agents (glycolic acid, gluconic acid, ethylenediaminetetraacetic acid, and citric acid) were used for the dyeing of polyester fabrics with metal sensitive disperse dye in closed dyeing process. The chelating and pH adjustment efficiencies were compared in disperse dyeing condition. In the comparative analysis with different chelating agents, glycolic acid showed a higher chelation efficiency and consequently showed higher dye bath exhaustion and color strength. Slight differences in the color fastness of the dyed samples obtained by employing four different chelating agents were observed.

Dyeing of cotton and polyester blended fabric previously cationized with synthetic and natural polyelectrolytes

In this work, a plain weave composed by 50% polyester and 50% cotton (PES/CO) was functionalized by using two polyelectrolytes, in order to modify its surface to provide a dyeing with an uncommon dye class for cotton and polyester fibers. Several techniques of characterization were used to study the effects caused by the interaction between polyelectrolytes (Chitosan and PDDACl) and PES/CO fabric, such as: X-ray Photoelectronic Spectroscopy (XPS), dye solution drop absorption, Scanning Electron Microscopy (SEM) and whiteness by Berger degree. Good results of dyebath exhaustion with excellent values of color strength were obtained for the samples previously treated with PDDACl and Chitosan polyelectrolytes. These promising results mean the possibility of obtaining distinct and solid colors that cannot be obtained with the use of dispersed/reactive dyes, besides generating a lower energetic cost with the use of lower times and temperatures than those normally used to PES/CO dyeing process.

Dyeing Behavior of the Cellulosic and Jute Fibers with Cationic Dyes: Process Development and Optimization Using Statistical Analysis

ABSTRACTThe aim of this study is to improve the dyeing behavior of cotton and jute fibers using natural product as surface modifying agents to the cationic dyes. Surface modifications have been performed on both cellulosic and jute used in this work by different types of chemical and natural products. Present study has been concerned with the evaluation of dyeing quality by controlling the percentage of dye bath exhaustion, the color yield (k/s) and the color fastness to light, washing and rubbing. In addition, optimization dyeing process was performed using a surface design with the help of Minitab 15 Software.

Synthesis of Novel Acid Dyes with Coumarin Moiety and Their Utilization for Dyeing Wool and Silk Fabrics

This article describes the synthesis of some novel coumarin compounds to use as acid dyes by using compounds 1 - 4 as starting materials, which were prepared by interaction of 2-hydroxybenzaldehyde with ethyl 3-oxobutanoate, diethylmalonate, 4-nitrobenzenediazonium chloride and 4-sulfobenzenediazonium chloride, respectively. Compound 1 reacted with bromine and 2-cyanoacetohydrazide to give phenacyl bromide derivative 5 and 2-cyanoacetohydrazone derivative 6, respectively. Coupling of compound 6 with equimolar amount of 2-sulfo-4-((4-sulfophenyl) diazenyl)benzenediazonium chloride gave coumarin acid dye 8. Phenacyl bromide derivative 5 re-acted with potassium cyanide in refluxing ethanol to produce compound 7, which on coupling with equimolar amount of 8-hydroxy-6-sulfonaphthalene-2-diazonium chloride and 8-hydroxy-3,6-disulfonaphthalene-1-diazonium chloride gave coumarin acid dyes 9 and 10, respectively. Interaction of compound 2 with 2-amino-5-((4-sulfophenyl)diazenyl)benzenesulfonic acid, benzene-1,4-diamine and 3,3’-dimethoxy-[1,1’-biphenyl]-4,4’-diamine in refluxing ethanol afforded compounds 11, 12 and 14, respectively. Diazonium sulphate of compounds 12 and 14 coupling with 4-amino-5-hydroxynaphthalene-2,7-disulfonic acid gave compounds 13 and 15, respectively. Cyclocondensation of compound 3 with ethyl 3-oxobutanoate, diethyl malonate and malononitrile afforded derivatives of 3-acetyl-2H-chromen-2-one 16, ethyl 2-oxo-2H-chromene-3-carboxylate 17 and 2-imino-2H-chromene-3-carbonitrile 18, respectively. Reaction of sodium benzenesulfonate derivative 4 with ethyl 3-oxobutanoate and hydrazine hydrate gave compounds 19 and 20, respectively. The structures of the newly synthesized compounds were confirmed by elemental analysis, UV/ VIS, IR, 1H NMR and Ms spectral data. The suitability of the prepared dyestuffs for dyeing of wool and silk fabrics has been investigated. The dyed fabric shows good light fastness, very good rubbing, perspiration, washing and excellent sublimation fastness. These dyes have been color shade from blue to violet with very good depth and levelness on fabrics. The dye bath exhaustion and fixation on fabric has been found to be very good.

Study of Hydrophilic Modification for Polyamide 6,6 and its Characterization

Polyamide 6,6 (PA 6,6) fiber is amongst the most substantial chemical fibers useful in a wide range of apparel and industrial applications. Overlooking the benefits, the poor hydrophilic nature of this fiber cause wet processing crucial and unsatisfactory ease of wearing for clothing. In this work, the surface modification of PA 6,6 fiber were studied by using Subtilisin and Alkali (NaOH). The effects of modification were investigated, including amino group determination by wool reactive dyeing, the surface morphology and chemical analysis by Scanning Electron Microscopy-Energy Dispersive Spectrometer (SEM-EDS) and Attenuated Infra-Red (ATR-IR). The dye-bath exhaustion and color strength results confirmed the increased amount of amino groups formed after modifications. The increased oxygen content in SEM-EDS results indicates the possible formation of carboxyl group after modifications. Generally, both Subtilisin and alkali treatments resulted in improvement of hydrophilicity and other properties of PA 6,6 fabrics; although Subtilisin treatment considered as clean and eco-friendly treatment in regards of environmental matters.

Ionic Liquids Can Significantly Improve Textile Dyeing: An Innovative Application Assuring Economic and Environmental Benefits

Owing to economic reasons, the textile dyeing industry generally employs traditional and absolutely no-eco-friendly processes: very large quantities of water are indeed required together with a large number of added chemicals which represent dramatic environmental issues. In order to improve the sustainability of the process, we have investigated the dyeing of wool, polyester, and cotton with disperse Red 13 using ionic liquids as the sole additive. The results obtained in isothermal dyeing at 95 °C show an outstanding effect of the ionic liquid 1-(2-hydroxyethyl)-3-methylimidazolium chloride. This ionic liquid assures efficient dyeing of polyester and wool in open vessels, in the absence of whichever auxiliary agent with total dyebath exhaustion, thus allowing in principle the recycling of the dye bath! The environmental benefits arising from the substitution of a number of usually employed auxiliary agents with only an ionic liquid are highlighted together with the economic ones. This article reports for the first time, to the best of our knowledge, dyeing processes for several kinds of fibers (cotton, wool, and polyester) employing exclusively three components: pure disperse dye, water, and an appropriate ionic liquid.