Dyeing Of Polyester Research Articles

Microwave Assisted Synthesis of Some Azo Disperse Dyes part 3: Dye bath Reuse in Dyeing of Polyester

Due to the environmental risks that humans may be exposed to, whether from nature or industrial waste, in this study the water resulting from the dyeing bath was treated with sugarcane bagasse to reduce damage to the environment. Waste water of dye bath was also used to dye the polyester fabrics

Effective reduction clearing parameters involving alternative reducing agent

Dyeing of polyester is done by using disperse dyes. Some of the disperse dyes remain unfixed during dyeing and create problems in shade and colorfastness properties. Reduction clearing (RC) is a process to remove these unfixed dyes and to enhance colorfastness properties. In the Pakistani textile industry, reduction clearing is being done by using sodium dithionite (Na2S2O4), which has the best results in reducing dyestuff. The problem with sodium dithionite is that it is sensitive to air and also creates a lot of environmental issues. Its sensitivity causes inconsistent results of reduction clearing. Different dyers used different processes and recipes of reduction clearing. Thiourea Dioxide (TUD) is a green reducing agent and can be used as a replacement for sodium dithionite. TUD (CH4N2S) is a stable product with a comparable result with sodium dithionite. Interlock knitted fabric is used in this project whose composition has recycled polyester. The fabric was first dyed using black dyestuff and then reduction clearing was done on a lab-scale with different factors (Shade depth, the concentration of TUD, RC temperature). Three colorfastness tests were conducted to evaluate the different levels of each factor i.e. colorfastness to washing, fastness to perspiration, and fastness to water according to standard numbers ISO 105-C06, ISO 105-E04, and ISO 105-E01, respectively. It was observed that shade depth does not affect the results while concentration and RC temperature have a significant effect on the results. Moreover, the effective concentration of TUD was also determined.

An investigation of process parameters on colour during the dyeing of polyester in supercritical carbon dioxide media

AbstractInnovative supercritical carbon dioxide (scCO2) treatment conditions in fluidised media technology were examined for polyester dyeing. The different dyeing processes in scCO2 media were carried out under a constant dyeing temperature of 120°C (at pressures ranging from 9 to 29 MPa), a constant pressure of 25 MPa (at dyeing temperatures ranging from 40 to 140°C) and a constant density range of 500‐550 kg/m3 (at combinations of dyeing temperatures ranging from 80 to 130°C and dyeing pressures ranging from 18 to 28 MPa). The constant dyeing temperature, constant dyeing pressure and constant density (120°C, 25 MPa, 500‐550 kg/m3, respectively) were selected according to the best results in the literature and recommendations from industrial applications for polyester dyeing in scCO2 media. The different conditions of the studied parameters and their influence are discussed. Colour difference (ΔE) and colour strength (K/S), as well as washing fastness and bursting strength properties, were investigated and compared. Acceptable colour properties (similar to those for standard [control reference] fabric: dyed in scCO2 media at 120°C, 25 MPa pressure and 506 kg/m3 density for 90 minutes) on polyester fabric, with commercially acceptable and quite high washing fastness levels and comparable bursting strength values (similar to those for standard fabric without significant or drastic strength loss), could be achieved with the following scCO2 dyeing processes: at a lower dyeing pressure with the same dyeing temperature (in scCO2 media at 120°C, 21 MPa pressure and 423 kg/m3 density for 90 minutes), at a lower dyeing temperature with the same dyeing pressure (in scCO2 media at 100°C, 25 MPa pressure and 588 kg/m3 density for 90 minutes) and at both a lower dyeing pressure and a lower dyeing temperature with a constant density range of 500‐550 kg/m3 (in scCO2 media at 110°C, 24 MPa pressure and 526 kg/m3 density for 90 minutes). Satisfactory and successful dyeing properties and performance similar to polyester fibre dyed under standard scCO2 dyeing conditions with less energy consumption could be achieved with the correct scCO2 dyeing process parameter optimisation. For instance, the dyeing process in the scCO2 environment at the same dyeing temperature with the standard scCO2 dyeing process (at 120°C), but with a lower dyeing pressure (at 21 vs 25 MPa), resulted in a 17 kWh decrease in energy consumption. In conclusion, it is very important to choose the correct dyeing pressure to obtain level dyeing in the polyester dyeing process carried out in a scCO2 environment and to achieve a reduction in energy consumption during dyeing in a scCO2 medium.

High-efficiency dispersant-free polyester dyeing using D5 non-aqueous medium

Conventional polyester dyeing with disperse dyes consumes a large amount of freshwater resource and requires a great deal of dispersant, which poses a major challenge to the dyeing and finishing industry. To meet the requirements of clean production and sustainable development, a modified decamethyl-cyclopentasiloxane (D5) non-aqueous medium dyeing system containing a little water was proposed in this study, and the effect and mechanism of a little water on the polyester dyeing were investigated. Both D5 and liquid paraffin non-aqueous medium dyeing systems containing approximately 50% (on weight of fabric, owf) water are observed to significantly improve the dye uptake of disperse dyes and the color strength of dyed fabric with excellent levelness and high colorfastness. The confocal laser scanning microscopy (CLSM) with fluorescent labeling technique confirms the accessibility of water in the surface layer of polyester fiber, and the dynamic thermomechanical analysis (DTMA) reveals the diffusion of water into the polyester fiber, thereby reducing the glass transition temperature (Tg) of polyester fibers by plasticization effect, promoting the movement of fiber molecular chain segments, and enabling the fixation stage of dyeing to be performed at a lower temperature. The dyeing principle of the modified D5 medium dyeing of polyester has enriched the theoretical system of non-aqueous medium dyeing, being conducive to facilitate the development of the sustainable dispersant-free and water saving polyester dyeing technology.

Development of multifunctional polyester using disperse dyes based through a combination of mosquito repellents

Advancement of new protection methodologies to counter mosquito-borne diseases always remains a public intrigue. Among all reported and researched methods, mosquito repellent textiles may prove an effective product, as textiles being the basic need, cover most parts of the human body. This investigation focuses on the synthesis of novel mosquito repellent dyes from a combination of mosquito repellents like N, N‑diethyl-3-methyl benzamide (DEET) derivative, ethyl anthranilate, and 4‑hydroxy coumarin. Resultant dyes were analysed by FTIR, 1HNMR, UV spectroscopy, mass spectroscopy, and elemental analysis. The synthesized dyes were utilized for the dyeing of polyester. Dyed polyester demonstrated 100% mosquito repellency along with other functional properties such as antibacterial activity (>93%) and UV protection (UPF>124). The mosquito repellency was retained to a significant extent even after 20 washes. The synthesized dyes also displayed an efficient antioxidant activity and low algal toxicity. As most of the textiles are coloured, the synthesized novel disperse dyes can act as a tool for the multifunctional modification of polyester-based textile substrates.

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.

Waterless beam dyeing in supercritical CO2: Establishment of a clean and efficient color matching system

Utilization supercritical CO2 to conduct the anhydrous dyeing of polymers, as one of the most important candidates instead of water dyeing, has been highly concerned by textile industry due to its environmental friendliness, energy preservation and recyclability of CO2 and chemicals. In order to investigate an efficient color matching database of supercritical CO2 dyeing, polyester dyeing was carried out with Disperse Red 54, Disperse Blue 79 and Disperse Red 167. The basic database of the three disperse dyes in supercritical CO2 was established using the Kubelka-Munk Theory with Single Constant. The results showed that the build-up curves of Disperse Blue 79, Disperse Red 54 and Disperse Red 167 at 610 nm, 480 nm and 520 nm are convex upwardly rather than straight. Large deviation between the calculated K/S data and the experimental ones of the dyed polyester is emerged because the color depth at the maximum absorption wavelength is affected by other dyes in supercritical CO2. By introduction of correction coefficients, less than 6 % deviation values between the calculated K/S values and the experimental ones can be obtained with the revised Kubelka-Munk Theory with Single Constant. The revised equation displays obvious potential application value to reduce the chromatic aberration in the color measurement and matching of supercritical CO2 waterless dyeing.

Review on Intermolecular Forces between Dyes Used for Polyester Dyeing and Polyester Fiber

Polyester fiber is a manufactured fiber composed of synthetic linear macromolecules in the chain at least 85% by mass of an ester of diol and benzene-1, 4-dicarboxylic acid (terephthalic acid). Fibers of the most common polyester, poly(ethylene terephthalate) (PET or PET), are generally made from either terephthalic acid or dimethyl terephthalate together with ethylene glycol. Dyeing of polyester fabric with disperse dyes, polyester requires the use of dispersing agents. The chemical characteristics and general application conditions of disperse dyes are characterized by the absence of solubilizing groups and low molecular weight. Dye particles have a size ranging from 0.5 to 2.0 microns, generally contain –NH2, substituted –NH2, or –OH groups in the structure, and get attached with the fiber through H-bond and van der Waals force. Dyes are retained by the fiber by physical forces. Fastness properties are very high in polyester except in certain cases. The dye-fiber (PET) affinity is the result of different types of interactions, such as hydrogen bonds, dipole-dipole interactions, and van der Waals forces.

Influence of dispersing agents on adsorption and desorption rate of a disperse dye on polyester

Dispersing agents play important roles in polyester dyeing with disperse dyes. The purpose of this work is to determine the influence of dispersing agents on the adsorption and desorption rate of polyester dyeing with CI Disperse Blue 284. Polyester fabric was dyed at HTHP method using two types of dispersing agents at different concentrations. The performances studied were the changes in dye transfer rate, K/S values of the dyed samples and dye bath concentration. The rate of adsorption and desorption of disperse dyes were affected significantly not only by the type but also the concentration of dispersing agents.

Modification of Polyester Textiles for Easier Dyeing with Disperse Dyes

Modification of polyester fibers for more economical dyeing at lower temperatures without a carrier are considered in this study. Polyester dyeing is carried out industrially under rigorous conditions at high temperatures and under increased air pressure, and are treated with various solvents (primary alcohols) to make the fibers more permeable. As a result, the sorption properties, as well as the disperse dye dyeing ability, are improved. Dyeing of a modified polyester fabric at lower temperatures yielded better results than the standard dyeing of the unmodified polyester under the same conditions. The effects of fiber modification were analyzed through water absorption properties, wetting, swelling, differential scanning calorimetry (DSC), and Fourier transform infrared (FTIR) methods, and the degree of dyeing of the fabric was evaluated using CIELab parameters.

Regenerated cationic dyeable polyester deriving from poly(ethylene terephthalate) waste

In this paper, sodium-5-sulfo-bis(hydroxyethyl)-isophthalate (SIPE) comonomer, which could copolymerized with bis(hydroxyethyl) terephthalate (BHET) for dyeability modification of poly(ethylene terephthalate) (PET), was prepared through transesterification reaction of sodium dimethyl 5-sulfoisophthalate (SIPM) and ethylene glycol (EG). The obtained SIPE was then polycondensation reacted with BHET which was extracted from waste PET fiber depolymerization under nitrogen atmosphere with excess EG as glycolysis agent and zinc acetate (Zn(Ac)2) as catalyst, to achieve regenerated cationic dyeable polyester (rCDP). Chemical structure, thermal properties, intrinsic viscosity and thermal properties of rCDP were analyzed and compared with virgin CDP (vCDP). Effects of SIPE on rheological property and dyeability of rCDP were also investigated.

Synthesis of 4-arylazo-2-(N-pyrazolylcarboxamido)thiophene disperse dyes for dyeing of polyester and their antibacterial evaluation

The current article aims to synthesize some new arylazo-thiophenes for dyeing polyester fabrics and screen their antimicrobial activities. The new 4-arylazo-2-( N-pyrazolylcarboxamido)-thiophene dyes 4a–e were prepared by the reaction of 2-acetyl-2-arylazo-thioacetanilide derivative 1 with 2-chloro- N-(3-methyl-1 H-pyrazol-5-yl)acetamide derivative 2. The structures of these prepared analogues were established via Fourier-transform infrared and 1H/13C nuclear magnetic resonance spectra. The synthesized dyestuffs were applied to polyester fabrics after establishing the optimal dyeing conditions at 130 ºC, high pressure, 3% shade, and liquor ratio 20:1 at pH 5. Furthermore, the dyed fabrics obtained under these optimal conditions resulted in proper colorfastness toward washing, rubbing, sublimation and perspiration, and were adequate for light fastness. They showed respectable antibacterial effectiveness against two bacterial strains, Staphylococcus aureus (Gram-positive) and Salmonella typhimurium (Gram-negative) bacteria. The dyed fabric with dye 4d displayed the best antibacterial activities with percentage reduction of 88% and 76% against S. aureus and S. typhimurium bacteria, respectively.

Polyester Dyeing and its Environmental Impact

Dyeing and printing of textiles are responsible for 30% of the pollutants contained in the effluents. The impact of textile dyeing processes on environment is highly variable, most important issues being the colour, the organic charge, and the solids in suspension. The present study investigates the characteristics of the polyester dyeing process in what concerns the environmental issues. Disperse dyes are non ionic, have very limited solubility in water at room temperature and have substantivity for polyester fibre. Two disperse dyes were used, and dyeing were performed at different concentrations. The exhaustion degree, the volume of wastewater used in the process, the specific flow, pH, temperature and chemical oxygen demand of the wastewater, the total residuum, volatile substances and the biological oxygen demand were determined in all the cases. The data obtained showed that the global pollutant content of the wastewater from disperse dyes dyeing is high (more than two times higher than those obtained in the case of dyeing with acid dyes). Absorption spectra of the initial and exhausted dyebath were determined, in order to evaluate the dilution degree needed to make wastewater colour acceptable.

Dyeing properties of orgonobase-induced poly(ethylene terephthalate) fabric

Polyester is the most used of the synthetic fibers used in the textile industry. Nonetheless, due to its structure, the use of only disperse dyes for dyeing creates a significant weakness in its coloring. In this paper, the utilization of reactive and acid dyes in the dyeing of polyester after chemical modification with guanidine-based polymer is investigated. The dyeing of poly(ethylene terephthalate) (PET) fabrics with reactive and acid dyes was succeeded via modification with guanidine-based polymer. The effects of this polymer on disperse dyeing were also investigated. The effect of various parameters such as temperature, duration, pH, different amounts of salt and alkaline, the different dyes and processes were investigated for modifying and dyeing PET. The optimum parameters for reactive dyeing were found to be modification and dyeing in the same bath at 100° C for 60 minutes without salt and alkaline, for which the obtained color strength (12.87) was higher than that of conventional disperse dyeing with carrier (10.43). In addition, polymer modification at 130° C for 60 minutes before disperse dyeing provided higher color depth (24.39) than dyeing of PET by the conventional disperse high temperature method (22.48). Color fastness in laundering and the perspiration of modified and reactive dyed fabrics reached good to excellent levels (4/5). The modified and dyed samples were characterized using Scanning Electron Microscopy and Fourier Transform Infrared. Tensile tests and flexural rigidity tests for modified and reactive dyed samples were also conducted. The results indicate that the quality of the beginning material was not degraded after being modified and dyed.

Dyeing of Polyester and Cotton Fabrics with Dispersedly Extracted Curcumin

Dyeing of Polyester and Cotton Fabrics with Dispersedly Extracted Curcumin

A novel approach for dyeing of polyester using non-aqueous deep eutectic solvent as a dyeing medium

PurposeTextile industry is considered to be one of the largest consumers of water. There needs to be an alternative for water in textile wet processing. Solvent dyeing can be an approach to replace the use of water in dyeing for water conservation.Design/methodology/approachIn this study, the dyeing of polyester was carried out using conventional and solvent dyeing methods. The solvent used was non-aqueous, deep eutectic solvent (DES) prepared using choline chloride and urea. Dyeing parameters such as time, temperature and pH were optimized for a concentration of dye using the solvent and were compared with the conventional dyeing.FindingsThe prepared solvent was characterized in terms of Fourier-transform infrared resonance and1H and13C nuclear magnetic resonance to analyze the reaction between choline chloride and urea. Dyeing performance in terms of K/S and fastness properties of dyed fabrics were evaluated and found to be at par against conventional dyeing.Originality/valueUse of DES as a dyeing medium is a novel approach in the textile industry.

Novel colored polyurethane nanoparticle for recyclable dyeing polyester fabric

Colored wastewater has to be treated before its discharge, which is a great challenge for the protection of the ecological environment. A novel polymeric dye with nanoparticle morphology has been handily designed to dye polyester fabrics and can be fully recycled to avoid a large number of dyes discharge. It solves the colored wastewater pollution problem in the dyeing process from the source. The colored polyurethane nanoparticles with an average size of 500 nm are prepared via emulsion polymerization. The average content of the colorant monomer on nanoparticle is 2.77%. The colored nanoparticle demonstrates no thermal degradation at 110 °C and no damage under 20 MPa, which means good adaptability for the high-temperature dyeing process. The color depth of dyed polyester fabric can be easily adjusted by changing the concentration of colored nanoparticles in dyebath. The colored nanoparticles in the residual dyebath can be collected by extraction filtration leading to the concentration decreases from 11 mg mL−1 to 0.000025 mg mL−1 after filtered. Both the colored polyurethane nanoparticles and filtered water are fully reused for the next dyeing process to achieve the purpose of avoiding water consumption and residue dyes discharged. This work can promote the development of green and clean dyeing processes in the textile industry.

Wastewater treatment using flocculation method and water reuse for dyeing of polyester fibers

Textile industry uses and pollutes large quantities of water, especially for chemical treatments of textile materials, like bleaching, desizing, dyeing, printing and finishing. After each process, the water is usually drained into the sewage system and fresh water is used for new process of textile treatment. Re-using of wastewater for further processing would be of great importance in term of saving fresh water and diminishing the environmental burden. The goal of our research was to find out whether treatment of dye-house wastewater with flocculation could be efficient enough for water re-use in further dyeing of polyester fabric.Wastewater collected in Slovenian dye-house was treated with a cationic flocculant. Treated water was analysed for chemical oxygen demand (COD), total organic carbon (TOC), spectral absorption coefficient (SAC) and dry matter and further used for laboratory dyeing of polyester fabric. The fabric was dyed comparatively using technological and treated water under the same conditions in light, medium and dark shade. The colour of dyed samples was evaluated on spectrophotometrically. Wet fastness and colour fastness to perspiration (acid and alkaline) of differently dyed samples were investigated. Change of colour was acceptable for all dyed samples. Fastness to washing and perspiration were good, very similar when comparing samples dyed in technological and those dyed in cleaned water. The colorimetric and fastness results showed a high efficiency of flocculation for dye-house wastewater treatment and reuse of treated water in production.

Synthesis of new azobenzene dyes clubbed with thiazolidinone moiety and their applications

Purpose The purpose of this paper is to synthesize some new azobenzene dyestuffs clubbed with thiazolidinone moiety and their solicitation in dyeing polyester fabrics representing their antibacterial evaluation. Design/methodology/approach Herein, the authors report the synthesis of new thiazolidinone moiety after the coupling of diazotized 4-aminoacetophenone with resorcinol. The newly synthesized dyes were characterized by IR, elemental analysis, mass spectroscopy and proton nuclear magnetic resonance (1H NMR) spectral studies. The characteristics of dyeing of these dyestuffs were evaluated at optimum conditions. Concurrent with dyeing of polyester fabric for synthesized dyes with their antibacterial activity was estimated. Antimicrobial activity of the dyed fabrics at different concentrations was evaluated against gram-positive and gram-negative bacteria. Findings Synthesized azobenzene dyestuffs clubbed with thiazolidinone dyes were applied on polyester fabrics. It was remarked that the modified dyes exhibited better colourfastness properties. Furthermore, the synthesized dyes revealed antimicrobial activity against gram-positive and gram-negative bacteria. Research limitations/implications The synthesized azobenzene dyes for polyester dyeing were not bore earlier. Practical implications The azobenzene dyes were accountable for giving improved colourfastness properties on polyester fabrics. Social implications The synthesized azobenzene derivatives are sensibly expensive and applicable dyes accompanied with good antimicrobial and anticancer activities. Originality/value A common process could be affording textiles of colour and antibacterial assets. The newly synthesized dyes containing thiazolidinone moieties with azobenzene coupler showed interesting disperse colourant for polyester with good antibacterial activity.

Colorimetric Analysis of the Stability of Annatto Dye in Solution and Its Use in the Dyeing of Polyester Fibers

Due to the large amount of toxic effluents generated by the textile industry using most of synthetic dyes, natural dyes are increasingly gaining prominence, in keeping with the global trend toward prioritizing the use of cleaner technologies. However, the application of natural dyes is still restricted, mainly due to their instability in solution and poor fixation onto textile substrates. Thus, research is required to improve the performance of these dyes in order to obtain products with the characteristics desired by the industry. In this study, the potential of natural annatto dye in the dyeing of polyester (PES) fiber was analyzed and the color and stability parameters in solution were evaluated through two experiments. Initially, the stability of the natural annatto dye in solution was determined under different conditions of temperature, pH, and dye concentration and the application of this dye in conventional PES fiber dyeing was investigated. Subsequently, the influence of the use of a carrier in the dyeing of PES fiber was evaluated. The results indicated that the variables with the greatest effect on the degradation of the dye are temperature and pH. The natural annatto dye showed good interaction with the PES fiber in the conventional dyeing process, presenting good results of color yield and levels of fastness. In the dyeing processes conducted with and without a carrier, the dyeing performed in the latter provided better results, with the advantage of allowing the application of lower temperatures.