Dyeing Of Polyester Research Articles

Study of Fluorescent Dyeing Process and Influence of Mixture Dyes on High-visibility

In this paper, we present the results of an investigation and analysis of an experimental study of fluorescent disperse dyes used for dyeing polyester fabrics to high-visibility colors. This paper describes the results of spectrophotometric color measurements for yellow luminous, red luminous and orange luminous fluorescent dyes and their matching with the requirements of the EN 471 standard. The results of this study showed that the adsorption isotherms of polyester dyeing with fluorescent disperse luminous dyes follow the Nernst equation; the Nernst constants were determined and interpreted. The adsorption kinetics of fluorescent disperse dyes on polyester is studied by using the peudo-first-order model, the pseudo-second-order equation and the intraparticle diffusion equation. The results show that pseudo-second-order models fit well the experimental data with higher average regression coefficients (R2> 0.98). They also show that high-visibility is influenced by the dye concentration, and that the dye mixtures can affect the high-visibility.

Dyeing of polyester and polyamide at low temperature using solvent crazing technique

Partially oriented yarns of polyester and polyamide of two different deniers were simultaneously drawn and dyed on the melt spinning unit using solvent crazing technique at room temperature and just above their corresponding glass transition temperature with crude disperse dyes dissolved in benzyl alcohol. The same yarns were dyed by conventional methods with commercial disperse dyes after converting them into fully drawn yarns. The depth of dyeing obtained by solvent crazing technique was more than the dyeing of yarn by conventional method without any adverse effect on the fastness and mechanical properties. The depth of the shade did not change even after running the yarn for 600 meters indicating that thousands of meters of these yarns could be dyed while manufacturing without any shade variation. The proposed process can be used to reduce the consumption of energy as well as saving of cost that is incurred during manufacturing of commercial disperse dyes.

Dyeing of Polyester and Polyamide Synthetic Fabrics with Natural Dyes Using Ecofriendly Technique

This work presents an ecofriendly method for dyeing synthetic fabrics with natural dyes using UV/ozone pretreatment to activate fiber and improve dyeability of polyester and nylon. Fabrics are pretreated with UV/ozone for different periods of time ranged from 5 min to 120 min. Effect of pretreatment on surface morphology was studied by scanning electron microscope (SEM). Mechanical behavior was studied by testing tensile strength and elongation percentage. Chemical modification of the surface was studied using attenuated total reflection Fourier transform infrared spectrometer (ATR-FTIR). Dyeability of the treated samples was investigated in terms of their colour strength expressed as K/s in addition to fastness to washing and light. This research showed the increment of the affinity of the studied synthetic fabrics towards curcumin and saffron natural dyes using ecofriendly technique.

Facile Bifunctional Dyeing of Polyester under Supercritical Carbon Dioxide Medium with New Antibacterial Hydrazono Propanenitrile Dyes

In this work, new hydrazonopropanenitrile dyes with potential antibacterial activity were applied for dyeing polyester fabrics with supercritical carbon dioxide as a dyeing medium. The experimental conditions were optimized to obtain both visibly and spectrophotometrically uniform dye uptakes in the fabric. Raman microspectroscopy firmly indicated the dye uptake through all layers of the fabric. The color strength of the fabric was evaluated by K/S measurements and proved to be higher than those of conventional dyeing. The fastness properties of the dyed fabric were evaluated and found to give excellent results. The antibacterial test was performed according to the AA-TCC method, and the results were recorded.

Practical realisation of ozone clearing after disperse dyeing of polyester

In this study, a novel system utilising ozone in jet dyeing machines is introduced, and the results of ozone‐clearing treatments of disperse dyed polyester on the prototype modified machine are reported. A Venturi injector was mounted on the liquor circulation pipe of the jet dyeing machine to feed ozone gas into the machine. Ozone was generated via an ozone generator by feeding conditioned air into the generator. The ozone gas entering the pipe partly dissolved in the treatment liquor; the dissolved portion and the gaseous ozone interacted via the fabric in the pipe, especially in the nozzle and also at the bottom of the autoclave (machine body). Disperse dyed polyester fabrics of textile‐company mass production were ozone cleared in this prototype. Ozone clearing was achieved in cold water (room temperature), and no other chemicals were used. The colour of the samples, wet fastness properties, and the chemical oxygen demand of the effluent were investigated, and costs were compared with those of conventional reduction clearing of ozone. Results were outstanding: an 83% cost reduction, 67% timesaving, and an 88% COD reduction were achieved.

Cationic dyeing properties of trilobal high dimethyl 5-sulfoisophthalate sodium salt (SIP) content cationic dyeable polyester (THCDP) fabrics

To make the polyester ionically dyeable, trilobal high dimethyl 5-sulfoisophthalate sodium salt (SIP) content cationic dyeable polyester (THCDP) was developed in this study which aimed to investigate its structural and dyeing properties. Its lower glass transition temperature and crystallinity degree contributed to lower dyeing temperature. A low-cost and environmentally friendly dyeing solution was applied in this study and the dyeing temperature of newly THCDP fabric could be reduced to 90°C, distinctly different from the previous cationic dyeable polyester which needed more than 100°C to reach dyeing standard. Meanwhile, THCDP showed its higher dyeing saturation value than normal acrylic fabric and cationic dyeable polyester with the Cationic Red X-GRL dyestuff. In present, both pure THCDP and blend textiles were developed. A series of THCDP/Cotton blends’ (20/80, 35/65, 65/35, 80/20) dyeing behaviors were tested, and found they could be dyed at 90°C with good color fastness and levelness.

Synthesis and Application of Novel Reactive Disperse Dye Based on Tetrahydrobenzo[b] Thiophene Moiety

Ethyl 2-diazo-4, 5, 6, 7-tetrahydrobenzo[b] thiophene-3-carboxylate is reacted with malononitrile to give a hydrazone derivative. The latter product is reacted with 1-diazobenzene-4-β-sulphatoethylsulphone (PABSES) to give a disperse dye. The dye is synthesised by diazotisation and coupling reactions. First, it is synthesised with the chromophoric moiety of ethyl 2-hydrazomalononitrilo-4,5,6,7-tetrahydrobenzo[b] thiopheen- 3-carboxylate and coupled with diazonium salts that have the aforementioned reactive groups, thus yielding the new target reactive. The synthesised dye is applied onto wool, polyester and wool-polyester (blend) fabrics under typical exhaust dyeing conditions and their dyeing properties are investigated. The structure of this dye is characterised and confirmed by melting point, elemental analysis, infrared, ultraviolet-visible spectroscopy (UV/VIS) and nuclear magnetic resonance (1H-NMR) data. The dyeing of polyester, wool and polyester/wool blend fabrics with a reactive disperse dye gives very good build up and fastness properties by using a nonionic vinylsulphone (VS) derivative, which increases the substantivity of the dye towards wool fabric. Maximum exhaustion as well as total fixation efficiency by using a sulfatoethylsulfone (SES)-based dye on wool fabric is achieved at a neutral pH of 7. This feature of the dye structure significantly improves the union dyeing of wool/polyester blend fabrics with very good build up and fastness properties.

Dyeing behaviour of THCDP and its blend with cotton at low temperature

Tg and crystallinity of trilobal cationic dyeable polyester (THCDP) and poly(ethylene terephthalate) through X-ray diffraction and differential scanning calorimetry were tested respectively, and the results manifest that lower Tg and percent crystallinity of THCDP contribute to lower dyeing temperature. The dyeing behaviours of cationic black X-FDL on THCDP were studied, demonstrating that dyeing temperature of newly THCDP fabric can be reduced to 90°C, different from the previous cationic dyeable polyester, which needs >100°C to reach dyeing standard. A series of THCDP/cotton blend (20/80, 35/ 65, 65/35, 80/20) dyeing behaviours were tested successively via online monitoring dyeing system, and it has been found that they can be dyed at 90°C with good colour fastness and levelness.

Coloring properties of novel 1,4-distyrylbenzene and 4,4′-distyrylbiphenyl fluorescent brighteners and their arrangement in cotton and polyester fiber

Some novel 1,4-distyrylbenzene (DSB) and 4,4′-distyrylbiphenyl (DSBP) fluorescent brighteners (FBs) were used to dye polyester and cotton fabrics. The CIE whiteness, color hue and reflectance spectrum of dyed fabrics were compared. DSBP derivatives could dye the cotton and polyester fabrics with a higher whiteness level and had a lower fluorescent quenching concentration than DSB derivatives. The color hue for the fabric dyed with DSB FBs was yellow-green, whereas that dyed with DSBP was blue–violet. The molecular arrangement in the fiber had a significant influence on their optical properties, resulting in different coloring properties. The increase in molecule planarity and rigidity generated by the interaction between the polymer and FB molecules caused a remarkable bathochromic shift in emission and excitation spectra. The H-aggregate of the DSB molecule in the fiber was easily generated, and the degree of aggregation increased with the molecular polarity. However, the aggregation of DSBP molecules in the polyester and cotton fiber was not found. The surface region of the cotton fiber was filled with FB molecules, whereas FB molecules in the polyester fiber aggregated easily, and incident light could pass through the surface region.

Synthetic textile dyeing wastewater treatment by integration of advanced oxidation and biological processes – Performance analysis with costs reduction

Color and organic matter removals from acrylic, cotton and polyester dyeing wastewaters were evaluated by biological oxidation in a sequential batch reactor (SBR) and by integration of Fenton’s reaction with SBR. Raw and chemically oxidized pre-treated wastewaters were fed into the biological reactor during 10 cycles (i.e., up to pseudo-steady state conditions). Because the biological degradation did not allow obtaining effluents complying with the discharge limits, neither did the chemical oxidation per se, coupling the SBR after chemical oxidation was required. In the integrated chemical-biological process a new strategy was applied in the optimization of Fenton’s oxidation, consisting in the application of the optimum doses of Fe(II) and H2O2 (for biodegradability enhancement and maximization of color and DOC removals), but with the simultaneous objective of minimizing the operating costs. The integration of Fenton’s oxidation with a downstream SBR provides much better removal of organic matter (88–98% for COD, 83–95% for BOD5 and 91–98% for DOC, values depending on the particular textile effluent being used) and color (>99%) than the biological or chemical treatment alone could do. Besides, such an integrated treatment allows treated wastewaters to meet the discharge limits with a reduction of the operating costs, in the range 24–39% comparatively to Fenton’s oxidation alone.

A novel eco-friendly colorant and dyeing method for poly(ethylene terephthalate) substrate

Although madder (Rubia tinctorum) has been used as a well-known natural textile dye source for dyeing of natural fibers such as wool, silk and cotton, 100 % polyester dyeing with madder is not common. In this study, polyester samples were dyed with madder at different dyeing temperatures, from 60 °C to 130 °C, in company with 7 chemical and 5 natural mordants. Color properties and rub, light and wash fastness performances were investigated. Different shades of orange, brown, pink and reddish green colors were obtained. Dyeing at 130 °C exhibited the highest color yield, the highest chroma and the lowest lightness values. Overall, chemical mordants exhibited higher color yields than natural mordants. High wash fatness, moderate light and rub fastness levels were observed. The potassium bitartrate and gallnut, a natural mordant, exhibited the best results. The madder dyeing of polyester should be carried out at hot temperature conditions, 130 °C, in order to obtain the highest achievable color yield and chroma with the highest light and wash fastness properties.

Optimising by response surface methodology the dyeing of polyester with a liposome‐encapsulated disperse dye

Optimisation of conditions for dyeing polyester with liposome‐encapsulated CI Disperse Red 50 was performed using response surface methodology. The effects of temperature, time, and lecithin:dye ratio on the colour strength of dyed fabrics were investigated by a central composite design. The coefficient of determination, the probability value in analysis of variance, and the normality plot of residuals demonstrated sufficient significance of the proposed fitness function. It was found that the temperature and time of the dyeing cycle were effective factors in the dyeing of polyester fabrics with encapsulated dye. It was also established that the colour yield of dyed fabrics was above 25 in the case of a dyeing time of >80 min, a lecithin:dye ratio of ≤2, and a temperature of ca. 128 °C. Comparison of colour strengths produced by liposome‐encapsulated dye and commercial dye revealed that there was approximately the same build‐up on polyester. Dyeings from encapsulated CI Disperse Red 50 exhibited very similar fastness to dyeings from conventional CI Disperse Red 50.

Technical and economic feasibility of polyester dyeing wastewater treatment by coagulation/flocculation and Fenton's oxidation

This study aims to investigate the efficiency of individual and integrated processes applied to organic matter abatement and biodegradability improvement of a polyester dyeing wastewater, namely coagulation/flocculation combined with Fenton's reagent (Approach 1), Fenton oxidation alone (Approach 2) and its integration with coagulation/flocculation (Approach 3). The effects of Fe2+ dose, initial concentration of the oxidant (H2O2) and temperature during Fenton's oxidation were evaluated in Approaches 1 and 2, whereas in Approach 3 the influence of pH and flocculant dose was also assessed, during the coagulation/flocculation stage. Toxicity and biodegradability of the final effluent were also evaluated. After oxidation, a slight increase in the specific oxygen uptake rate of the effluent was observed (from 27.0 up to 28.5–30.0 mg O2/(gVSS h)) and the inhibition to Vibrio fischeri was eliminated. An effluent that complies with discharge standards was obtained in all cases; however, Approach 3 revealed to be a promising solution for treating this effluent as it leads to smaller operating costs. Therefore, the use of dissolved iron resulting from Fenton's oxidation as coagulant in the second stage was shown to be an innovative, efficient and economically attractive strategy for treating these effluents.

Study on Alizarin Dyes on Polyester-Cotton Knitted Fabrics Dyeing in Supercritical CO2

Using natural alizarin dyes to dye polyester - cotton65/35 knitted fabric in supercritical CO2 dyeing equipment, and analysis the influencing parameters including dyeing temperature, time and pressure. The parameters are optimized as following: dyeing temperature 115.21°C, dyeing time 71.42 min and dyeing pressure 26.22 Mpa. Adopting alizarin dyes to dye polyester-cotton65/35 knitted fabrics in supercritical CO2 could obtain a good dyeing effect, and the color fastness to rubbing and color fastness to washing of dyed fabrics meet The National Standard (GB18401-2003).

Optimization and Economic Analysis of Textile Wastewater Treatment by Photo-Fenton Process under Artificial and Simulated Solar Radiation

The degradation via the photo-Fenton process of dyes and organic compounds present in acrylic, cotton, and polyester dyeing wastewaters was investigated, aiming at reducing the consumption of chemicals, as compared to the dark Fenton process, while simultaneously minimizing the energy costs by using simulated solar radiation. The reduction of the hydrogen peroxide dose is limited by the need of achieving treated effluents complying with discharge limits, but for dark Fenton the operating costs are excessive. The costs associated with the use of artificial radiation in the photo-Fenton process (17.4, 9.6, and 2.9 €/m3 for acrylic, cotton, and polyester effluents, respectively) are also too high. The use of (simulated) solar light allows for obtaining high degrees of removal of color (>98–99%) and significant COD (30.1–72.0%) and DOC (46.2–71.5%) reductions at a total cost reduction of a factor of ca. 3. Treated effluents by the solar photo-Fenton process also meet the discharge standards.

Supercritical Dyeing Polyester Fibres with Disperse Dyes

Three thiadiazolyl azo dyes were used as disperse dyes for polyester fibres. The dyeing medium was supercritical CO2. The experiment conditions were 80 to 120°C and 2500 to 4000 psi pressures. The dyeing results were compared with traditional dyeing in water. The results shown that the disperse dyes have high substantivity towards polyester fibres and very good fastness.

Preparation and characterization of poly(ethylene terephthalate) copolyesters modified with sodium‐5‐sulfo‐bis‐(hydroxyethyl)‐isophthalate and poly(ethylene glycol)

ABSTRACTTwo types of poly(ethylene terephthalate) (PET) copolyesters were successfully prepared with sodium‐5‐sulfo‐bis‐(hydroxyethyl)‐isophthalate (SIPE) and poly(ethylene glycol) (PEG) units with different molecular weights named as cationic dyeable polyester and easy cationic dyeable polyester. Their chemical and crystalline structures were characterized by the nuclear magnetic resonance (NMR), wide angle X‐ray diffraction (WAXD), and small angle X‐ray scattering measurement, and their thermal properties were tested by differential scanning calorimetry and thermogravimetric analysis, respectively. NMR experimental results showed that the actual molar ratio of comonomers was basically consistent with the correlative feed ratio. WAXD results indicated that the crystalline structures of prepared copolyesters were similar to that of PET. Moreover, the glass transition temperature, melting temperature, and thermal degradation temperature were found to decrease with the reduction of the of PEG units as the incorporation of lower of PEG units brought more ether bonds into molecular chains, which increased the irregularity of molecular chain arrangement and led to lower crystallinity. In addition, because the incorporation of PEG units with lower molecular weight led to more ether bonds and hydroxyl end‐groups in molecular chains, the value of contact angle of PET copolyesters dropped, manifesting PET copolyesters had better hydrophilicity with the decreasing molecular weight of PEG units.© 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39823.

Dyeing of multiple types of fabrics with a single reactive azo disperse dye

AbstractThree novel reactive azo disperse dyes were prepared using 7-acetamide-4-hydroxy-2-naphthalene sodium sulphate as the precursor. The structure of the dyes has the combined characteristics of reactive, disperse, and cationic dyes. Under alkaline conditions (pH 9), the dyes can be applied to cotton, silk, wool, and nylon. Under neutral conditions, they can be used to dye polyester. Under acidic conditions (pH 4.5), they can colour acrylic fabric after conversion of the tertiary amine group to the quaternary ammonium cation. The colour-fastness of the dyed fabrics were also evaluated.

Substitution of Reduction Clearing Step by Ozone Treatment at Disperse Dyeing of Polyester

The effectiveness of ozone treatment for the afterclearing of disperse dyed poly (ethylene terephthalate) (PET) fibers has been examined. Two types of disperse dyed PET samples were selected among commercial mass production range of Akbaslar textile mill. The reduction clearing procedure applied during mass production was taken as the reference reduction clearing treatment; these reference samples were taken after dyeing and reduction clearing processes at the mill. Samples of disperse dyed PET were also taken before reduction clearing in order apply ozone treatment in the laboratory as the tested afterclearing method. Color and wash-fastness properties of the reduction cleared and ozone treated fabric samples were compared and reported. Results indicated acceptable color and wash-fastness results comparable to those of reduction cleared samples for ozone treated samples. The success of ozone treatment for the black dyed PET sample at 7.0% depth of shade was especially outstanding. Ozone treatment was applied in cold water without addition of any chemicals for very short treatment times when compared to conventional reduction clearing. Ozone treatment created substantial energy and chemical savings as well as lower environmental impact.

Treatment of textile dye wastewaters using ferrous sulphate in a chemical coagulation/flocculation process

The coagulation/flocculation treatment using FeSO4·7H2O as a coagulant is evaluated in this work for the removal of organic compounds and colour from synthetic effluents simulating the cotton, acrylic and polyester dyeing wastewaters. The coagulant dose, temperature, pH, stirring speed and stirring time that maximized the removal of dissolved organic carbon (DOC) and colour for each effluent are determined for the coagulation process. The effect of the stirring speed, stirring time and the dose of flocculant (Magnafloc 155 or Superfloc C-573) on the flocculation stage is also evaluated for effluents pretreated by coagulation at the optimal conditions previously determined. The obtained results showed that the optimal operating conditions are different for each effluent, and the process (coagulation/flocculation) as a whole was efficient in terms of colour removal (∼91% for cotton, ∼94% for acrylic effluents; polyester effluent is practically colourless). However, the DOC removal observed is not significant (∼33% for polyester, ∼45% for cotton and ∼28% for acrylic effluents). On the other hand, the remaining dissolved iron content is appropriate for further integrating the treatment with an iron-catalysed Fenton process, thus reducing the consumption of chemicals in the overall treatment.