Dyeing Conditions Research Articles

Effect of Ultra Violet (UV) Irradiation as an Environmentally Friendly Pre-Treatment on Dyeing Characteristic and Colorimetric Analysis of Wool

Low-energy UV lamps were used for the pretreatment of wool yarns and its effects were investigated in terms of surface morphology, tensile strength, and percentage dye uptake. Subsequently, raw and UV-treated wool yarns were dyed with Cochineal dye and the essential parameters affecting the dyeing process (i.e., temperature, pH, duration) were determined. The results showed that the color strength of the samples increased by (a) increasing the pre-treatment effectiveness (i.e., UV irradiation strength and its duration), and (b) increasing the influential dyeing parameters (i.e., higher temperature, higher initial dye concentration in the dye bath, longer dyeing time, and acidic pH). The UV irradiation pretreatment also enhanced the color fastness properties of the dyed samples under the same dyeing conditions. The results suggested that an eco-friendly, acid-free, and relatively cheaper dyeing process could be developed for the wool fibers pretreated with scalable and straightforward UV irradiation pretreatment.

Sustainable dyeing of wool fabric with Talaromyces purpurogenus

Natural dyes had been used by human being since ancient times for colouring of various materials including textiles. These were replaced completely by synthetic dyes, continuous use of which created the problem of pollution and environmental degradation. With the development of green technology and increased awareness of sustainability, the use of non-allergic, non-toxic and eco-friendly natural dyes on textiles has become a matter of significant importance. Among the natural sources of colourants, microorganisms such as bacteria and fungi have gained interest in the field of textile coloration. In the present study, the pigment solution yielded from growth of Talaromyces purpurogenus sp. on organic waste was used for dyeing of wool fabric. Under the dyeing conditions i.e. 1:30 M:L ratio, pH 5, 80º C temperature and 45 minutes dyeing time, the percent absorption could reach 57 %, 32%, 36% and 49% respectively. The wool fabric samples dyed with the fungal dye exhibited very good to excellent washing and rubbing fastness properties. The colour pigment obtained from fungal thus offered an opportunity to reduce impact on plant resources for dye source exploration. So it can be concluded from the study that a natural fungal dye could help to sustain the environment and to minimize the over exploitation of natural resources.

Preparation and stabilization of Ag nanoparticles with N-vinyl-2-pyrrolidone grafted-poly(vinyl alcohol) in an organic medium and investigation of their usability in the catalytic dye decolorization

To obtain a copolymer with different substituent groups, N-vinyl-2-pyrrolidone (NVP) was grafted onto certain appendages of vinyl methacrylate introduced-poly(vinyl alcohol) PVA using AIBN. Then, PVA-g-NVP copolymer was used in the formation and stabilization of Ag nanoparticles in an organic medium without the use of reducing agents. The effects of volume ratio of the solvents, temperature, and concentrations of reactants were investigated for the formation of Ag nanoparticles. The particle size distribution of the Ag particles was determined using the TEM technique. The dispersions of the Ag nanoparticles were used in the decolorization of Congo Red (CR) and Methylene Blue (MB), in the presence of an electron donor NaBH4. Satisfactory catalytic activity results (>85%) were obtained with lower amounts of Ag dispersions according to the dye concentration, and it was observed that the performance of the Ag nanoparticles changed depending on the type of dye and preparation conditions.

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.

Improvement of the Rubbing Fastness of Cotton Fiber in Indigo/Silicon Non-Aqueous Dyeing Systems.

In order to solve the poor rubbing fastness of dyed cotton fiber in the indigo/silicon non-aqueous dyeing system, the process parameters of the silicon non-aqueous dyeing system were optimized. Dyed cotton fiber was post-treated to achieve the optimum dyeing conditions for obtaining a better rubbing fastness. Meanwhile, the dyeing performance of cotton fiber in a traditional water bath and silicon non-aqueous dyeing system was compared. The results showed that the rubbing fastness of dyed cotton fiber in the silicon non-aqueous dyeing system (one dyeing) was lower than that of traditional water bath (twelve cycles), although the color depth of dyed cotton fiber was deeper. For obtaining a good rubbing fastness, the optimum temperature was about 70 °C and the optimal dyeing cycle was one. Moreover, fixing agents can significantly improve the rubbing fastness of dyed cotton fiber. Especially, cationic waterborne polyurethane had an optimal fixing effect on the dyed cotton fiber. Soft finishing would weaken the effect of fixing finishing on the dyed cotton fiber, but the softener can significantly improve the handle of dyed cotton fiber.

Synthesis of novel disperse dyes based on curcumin for the creation of antibacterial polyester fabrics

Purpose This study aims to synthesize some new curcumin containing Aroyl derivatives dyestuffs and study their application in dyeing polyester fabrics, rendering to their antibacterial evaluation. Design/methodology/approach Modification of curcumin dye was carried out by introducing benzoyl rings through coupling with curcumin. All newly synthesized dyes were characterized by elemental analyses and spectral data (IR, 1 H-NMR and MS). Moreover, the optimal dyeing condition was assigned. Antibacterial activities of the dyed samples at different concentrations of both dyes were studied against gram positive (Staph aureus) and gram-negative (Salmonellatyphimurium) bacteria. Findings Synthesized curcumin containing benzoyl dyes were applied on polyester fabrics. Meanwhile, these synthesized dyes showed reasonable results towards fastness properties at optimal conditions matching the curcumin dye. In addition to their good fastness assets, synthesized dyes displayed antibacterial efficacy towards both gram positive and gram-negative bacteria. The dyed polyester fabrics showed higher antibacterial efficacy after multiple events of washing. Research limitations/implications The synthesized benzoyl containing curcumin moiety was not described before. Practical implications Disperse dyes derived from curcumin were prepared via coupling of various diazonium salts of p-aminobenzaldhyde, p-aminoacetopheneone, p-aminobenzoic acid and p-aminobenzoyl chloride with curcumin. The resulting disperse dyes were applied on polyester fabrics at optimal conditions, and antibacterial efficacy of dyed fabrics were evaluated. Originality/value Curcumin being was used in food colouration and was effective for dyeing and antimicrobial finishing on textile fabrics. Novel antibacterial dyestuff containing curcumin moieties with benzoyl amine coupling components showed interesting colourant for polyester fabrics. This work introduced innovative disperse dyes for medical textile applications.

A review on source, chemistry, green synthesis and application of textile colorants

Abstract This review provides a critical description of sources, processes, chemistry and performance of colorants. Critical discussion on environmental challenges and sustainability of colorants industry is provided. A comparison of natural and synthetic colorants indicates that life cycle of natural colorants is relative greener but not economical. A feature of natural colorants is poor performance, which can be enhanced by the use of mordant. However, most of the mordant are compounds made from transition elements with toxic effects to the environment. Low performance may be due to instability of the colorants at the required dyeing temperature and difficulties in control of dye concentration during dyeing process. Research on improvement of colorant stability under optimum dyeing conditions is recommended as alternative to the use of mordant. Green production and application of colorants is proposed as a permanent solution to environmental challenges caused by colorants. This will lessen the pollution burden caused by colorants and its associated remediation costs. It is envisaged that the environmental challenges of natural colorants can be minimised through improved technology of extraction and the use of green solvents during extraction. Structural modification of the natural colorant together with the use of green mordant is proposed to improve the performance of the colorant. The production of synthetic colorants involves the use of non-renewable and non-green raw materials, which is highly associated with environmental and health problems. The use of renewable and environmental friendly raw material for production of synthetic colorants is recommended for sustainable colorant industry. Cashew nut shells liquid is suggested as a potential renewable and green raw material for synthetic colorants. Research on technological and economic viability of the use of cashew nut shells liquid as a potential material for synthesis of colorants is proposed as a future research area.

A STUDY OF SUSTAINABLE COLORATION OF LYOCELL FABRICS USING EXTRACTS OF TROPICAL ONION SKINS

Lyocell is considered as a new fiber that represents a milestone in the development of environmentally sustainable textiles. Lyocell is spun from wood pulp cellulose via a green chemical process with NMMO (N-methylmorpholine-N-oxide) solvent. Following the concept of lower the environmental impact of fashion clothing, this study aims to determine the suitable natural dyes recipes with the color extracting from tropical onion skins. Colorants were extracted by dissolving crushed dried onion skins with boiled in water at 100ºC for 20-25 minutes. The ratio of extracting and dyeing are 1:25 and 1:30 respectively. The optimal dyeing condition was found out at 80ºC, 45 minutes with 75% v/v. In addition, a variety of the most commonly used mordants including Potassium aluminum sulfate, Copper (II) sulphate and Iron (II) sulphate were used for mordanting in order to compare the differently mordanted and unmordanted dyed fabrics via color strength (K/S) and CIE L*a*b* color values. It was found that mordant type had an effect on color strength and the color coordinates of fabric dyed with onion skin, which can supply variety of color choices for the same colorants.

Mn(II) oxidation and manganese-oxide reduction on the decolorization of an azo dye

The development of biological processes for treating azo-dye-contaminated waters is an important objective. Herein, we investigated the effects of Mn(II) oxidation and manganese-oxide reduction on the removal of the azo dye, Bordeaux S (BS), under aerobic and anaerobic conditions using two reactors, one with installed abiotic-MnO2, and one devoid of abiotic-MnO2. Under aerobic conditions, very little BS was removed, even at the highest Mn(II) oxidation rate (0.22 kg Mn(II) m−3 d−1), indicating that Mn(II) oxidation has essentially no effect on azo-dye removal. In contrast, under anaerobic conditions, the reduction and/or presence of MnOx was found to have an effect. Although BS decolorization increased with increasing K-medium loading, and the decolorization rate of 4.75 kg m−3 d−1 was achieved using both reactors, the reactor with abiotic-MnO2 performed better at low K-medium loading rates. The presence of MnOx induced higher secretion of extracellular polymeric substances, which serve as electron donors for the decolorization of BS under K-medium-deficient conditions. BS decolorization is caused by the simple cleavage of the azo bond to the 4-amino-1-naphthalenesulfonic acid moiety, and further degradation did not occur under anaerobic conditions. Although methane was produced even in the presence of MnOx, we conclude that Methanosaeta were inhibited.

Sustainable ultrasound-assisted ultralow liquor ratio dyeing of cotton fabric with natural turmeric dye

Natural dyes are environmentally friendly and have become important alternatives to synthetic dyes in some dyeing products. Therefore, better extraction and dyeing techniques need to be developed for the dyeing process of natural dyes. In this work, cotton fabric was dyed using turmeric extraction solution under an ultralow liquor ratio (materials to liquor ratio of 1:5) and ultrasonic-assisted conditions. Dye extraction using different dispersants and pH values has been investigated and three-factor-three–level Box–Behnken design was employed to explore the dyeing conditions. It was found that sodium dodecyl sulfate systems and ultrasonic waves can effective improve the dyeing depth under neutral condition. The K/ S value can reach 2.53 with ultrasonic power of 200 W, dyeing time of 30 min and temperature of 40℃. Scanning electron microscope images showed that the application of ultrasound did not cause obvious fiber damage. The developed technique could be used in the textile industry to make dyeing cotton fibers with natural dyes more sustainable than it is at present.

Optimizing enzymatic dyeing of wool and leather

This work reports on the environmental friendly enzymatic dyeing of wool and leather performed at low temperature and mild pH conditions without any dyeing auxiliaries. The substrates have been dyed with “in situ” generated pigment by means of laccase-catalyzed oxidative coupling of dye modifier 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) and dye precursor 1,3-benzenediol in a batchwise process. The process reaction variables (laccase, precursor and modifier concentrations, temperature and dyeing time) were optimized by response surface methodology using an appropriate experimental design. The temperature, precursor concentration, interaction between precursor and modifier and time are the most important factors in the dyeing process. The best-optimized wool dyeing conditions (2 h reaction time, 50 μl laccase (0.1 U), 500 mM precursor, 10 mM modifier at 40 °C) were then successfully applied onto leather material. The enzymatic-dyeing optimized process can be successfully performed on wool and leather at low temperature and mild pH obtaining different hues and depths of shades by varying the modifier concentration and time. The colouring enzymatic system has a good reusability (which has a huge advantage in terms of cost reduction) and washing durability and is comparable in terms of fastness properties to the traditional dyeing process for both wool and leather.

Cleaner pad-steam dyeing technology for cotton fabrics with excellent utilization of reactive dye

Abstract Developing a high utilization dyeing approach for cotton fabrics coloring is essential for the textile production in view of economic and ecological reasons. To enhance dye utilization and alleviate environment pollution, an industrializable pre-diffusion technique was applied to traditional pad-steam dyeing to enhance the effective reactions between fibers and reactive dyes. The appropriate dyeing conditions were determined. Dyeing mechanism was revealed by analyzing the speckle rates and reactive dye distribution within the padded fabrics. Dyeing properties, chemicals and energy consumptions, dyeing wastewater absorbance were measured and compared with conventional pad-steam dyeing. The appropriate dyeing conditions were recommended as follows: the padded fabrics were placed at 30 °C for 120 min to complete the pre-diffusion, and then fixed in atmospheric saturated steam for 4 min. The variation of speckle rates verified the change in free water of padded fabrics. Fabric cross-section indicated that the pre-diffusion procedure could improve reactive dye distribution. The recommended technology presented superior dyeing properties including dark color, high dye utilization and satisfactory color fastness. The reduction of about 8% dye, 12.5% Na2CO3 and 20% steam can be achieved using the developed dyeing technology. The absorbance of washing liquor using the recommended process was 0.29, about 65.9% lower than that of conventional pad-steam dyeing. The developed dyeing technology has distinct advantages of high dye utilization and lowly-colored dyeing wastewater discharge, which is conducive to saving chemicals and protecting the environment.

포도당 환원으로 천연 쪽 염색한 면직물과 아마직물의 염색 특성과 염색 견뢰도

This study was conducted to make help an environment-friendly dyeing method for natural indigo. In this study, glucose was used as a reducing agent for indigo. Four kind of fabrics composed of cotton fiber and flax fiber were used for this study. Dyeing with natural indigo was done under four different dyeing conditions having different pH levels and dyeing temperatures. Dyeing characteristics (color characteristics and color strength) and colorfastness were also measured. The dyeing differences in characteristics and colorfastness were analyzed based on the fiber type and dyeing condition. There were significant differences in color characteristics and color strength (K/S value) of fabrics dyed with natural indigo using glucose reduction based on the fiber type and dyeing condition. The K/S value of the fabric dyed with natural indigo through glucose reduction was the highest at 660nm. The colorfastness of the four fabrics dyed using natural indigo had a rate of 4 to 5 with the exception of rubbing fastness, which indicated good colorfastness.

Sustainable Functional Coloration of Linen Fabric Using Kigelia Africana Flower Colorant

ABSTRACT Natural dyes are gaining momentum in the textile industry due to their non-toxic and eco-friendly nature. The enhanced demand of natural-dyed functional textile materials resulted in increased interest among the research community to explore new sources of natural dyes which could be utilized for functional coloration of textile materials. Kigelia Africana flower is known for various medicinal properties and thus can be utilized for functional coloration of textile materials. In the current study, the pre-mordanting process has been exploited to evaluate the dyeing condition of the linen fabrics by using different mordants such as; alum, ferrous sulfate, and copper sulfate. The effect of mordants on the color strength of the dyed fabrics was analyzed and correlated with wash fastness tests results. The dyed fabrics analysis has been carried out in terms of their color strength and color coordinates (L*a*b*). The functional properties like radical scavenging activity, antibacterial activity, and UV protection properties were thoroughly investigated to determine the functionality of dyed fabrics. The dyed samples displayed satisfactory fastness and color strength along with efficient antibacterial, antioxidants and UV protection properties.

Synthesis of new thiophene dyes clubbed with sulfonamide for the creation of antibacterial polyester fabrics

The current study targets to synthesize some new sulfonamido-hydroxythiophene dyes for dyeing polyester fabrics with estimated antibacterial activity. The structure of sulfonamide dyes was adapted by conducting with sulfadimidine and sulfamethaxole through the coupling reaction. The synthesized derivatives were established by spectroscopic tools (Fourier transform infrared spectroscopy, proton nuclear magnetic resonance). Hydroxy-thiophene-containing sulfonamides were utilized for dyeing polyester fabric. The prepared sulfonamido-hydroxythiophene dyes were applied on polyester fabrics after establishing the optimum dye conditions, and afterward their dyeing properties, light, washing, perspiration, rubbing and sublimation fastness were determined. Meanwhile, the improved dyes demonstrated respectable fastness results and antibacterial properties against some gram-positive and gram-negative bacteria.

Right-first-time dyeing: a design of experiments approach for the optimisation of dyeing-processes using hard water

PurposeThe purpose of this study was to optimise the dyeing conditions to achieve right-first-time dyeing in hard water. Owing to the persistent water scarcity for more than two decades now, the textile industry in Pakistan is forced to rely on high-mineral-content ground water for use in textile wet processing. Furthermore, the limited amount of municipal water that is at the disposal of the textile industry is also high in mineral content. Thus, on the large scale, water hardness has become an acute problem for the textile processor. In particular, in the dyeing process, water hardness is known to have crucial effects. However, to-date, no systematic study has been conducted on this aspect of textile dyeing.Design/methodology/approachIn this study, 32 full factorial design was used to optimise the dyeing conditions to achieve right-first-time dyeing in hard water. Thus, cotton fabric was dyed with Red Reactive dye (of dyebath concentration at 5, 10 and 15 g/L) in prepared hard water (of hardness at 10, 40 and 70°dH), respectively. Analysis of variance, coefficient of determination (R2) and p-values for the models were used to evaluate the adequacy of the predictive models. The surface plots of the effects were studied to further examine the interactions of two independent variables. Derringer’s desirability function was used to determine the optimum levels of each variable.FindingsThree levels for both independent variables generate second-order polynomial models to predict the colour strength, lightness, red/green, yellow/blue and total colour difference values of dyed cotton. The obtained predictive models point out the considerable influence of both water hardness and dye concentration on right-first-time dyeing.Originality/valueSuch a finding enabled the dye-mill to produce the correct shade at water hardness of 10°dH and 15 g/L dye concentration, without the need for corrective reprocessing.

Structures and dyeing performances of polyethyleneimine-carbamate linked bamboo viscose fibers dyed with lac

Polyethyleneimine (PEI)-immobilization of bamboo viscose fibers using carbamate linkages (ABF-PEI) was investigated in order to improve the dyeing properties of the fiber. Results from morphological observation, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and thermogravimetric analysis clearly showed the successful carbamate binding of PEI at hydroxyl groups of cellulose fiber. The adsorption studies revealed that fast and efficient adsorption was achieved for ABF-PEI. Under optimum dyeing conditions, the amount of dye adsorbed on ABF-PEI at equilibrium (>100 mg/g) was much higher than that of the unmodified fiber (<10 mg/g). The adsorption behavior of lac dyeing on the PEI-modified bamboo viscose fibers could be described by the pseudo-second-order kinetics and Langmuir isotherm. The proposed mechanism mainly involved the electrostatic ion–dipole interaction between protonated amines of PEI and negative charged sites of lac dye. The color fastness results indicated good resistance of color changes for ABF-PEI, suggesting efficiency of the surface modifying method of PEI-immobilization on bamboo viscose fibers.

A Review on the Archaeological Chemistry of Shellfish Purple

Shellfish purple, also known as Tyrian purple and royal purple, has a long history, which has been revealed and documented in recent years through valid physicochemical studies using sophisticated techniques. The aim of the work was to summarize the conclusions of these studies and to describe the results of two unpublished investigations regarding the (i) identification of shellfish purple in a textile (4th century BCE) from ancient Macedonia and (ii) dramatic effect of the dyeing conditions on the composition of the purple dye. Moreover, a critical discussion is included about the discovery of the shellfish pigment and dye based on the available scientific evidence. Previously published reports describing the identification of the shellfish colorant in objects of the cultural heritage were carefully summarized. Shellfish purple was not used only as colorant, but it served other purposes as emphasized in this review. In particular, examples for the use of shellfish purple in medicine, grave goods and fillers and plasters in walls, were described. Examples of materials and methods that were used in the past to produce “fake” purple, imitating the aesthetic result of the valuable royal marine material were summarized. Finally, the solubility of indigoids was discussed using modern approaches of physical chemistry.

Harnessing natural colorants from algal species for fabric dyeing: a sustainable eco-friendly approach for textile processing

Little information regarding the utilization of algal-based pigments in textile industry is available despite their abundance in aquatic ecosystems, varying color nature, and relatively fast-growing habit than other photosynthetic organisms. The aim of the current study is to optimize the conditions in order to harness the colorants from selected marine algal species and evaluating their dye yielding potential for fabric dyeing. Cotton fabrics were dyed with aqueous, alkaline, acidic or organic extracts of four algal species, the brown algae Iyengaria stellata, Sargassum muticum, Colpomenia sinuosa, and the red alga Laurencia obtusa under varying conditions of temperature, pH, and exhausting agent concentration. Results showed that 4% KOH and 80% acetone extraction produced maximum color strength of dyed cotton fabric. Among the four species of algae used in the study, L. obtusa showed the highest yield of colorant. However, all four species extract behaved differently to dyeing conditions. Mordanting experiments results revealed that iron sulphate and tannic acid were excellent pre- and post-mordanting agents for producing darker color shades of cotton fabrics dyed with all the four algal species used in the study. FTIR analysis indicated that the dominant coloring agents in all four algal species were phenolics in nature. The fabric dyed with extract of I. stellata, C. sinuosa, and L. obtusa showed creamy white shade, while S. muticum-treated fabric produced light brown shade. Pre- and post-mordanting of algal powder dyed fabric with chemical mordants, particularly the tannic acid produced other shades, such as light and dark brown.

Supercritical CO2 dyeing for nylon, acrylic, polyester, and casein buttons and their optimum dyeing conditions by design of experiments

Supercritical carbon dioxide (scCO2) dyeing for textile and polymer processing is considered as a green and energy-saving process for view-points of environmental friendly and sustainable development. We developed a compact scCO2 dyeing apparatus and performed scCO2 dyeing for plastic buttons of nylon, acryl, polyester, and casein with a uniformly color at the temperature T, pressure P, and dyeing time t. The dye sorption in the buttons was examined by the dyeing color depth, which was evaluated by K/S values calculated from Kubelka-Munk equation. From the range analysis and variance analysis based on the Taguchi design of experiments, we found an optimum dyeing condition of K/S values for dyeing plastic buttons at T = 125 ℃, P = 27 MPa, and t = 80 min for nylon, T = 50 ℃, P = 14 MPa, and t = 40 min for acrylic, T = 120 ℃, P = 12 MPa, and t = 30 min for polyester, and T = 80 ℃, P = 10 MPa, and t = 30 min for casein, as well as the most influential factor and rank of influence factors for all plastic resin buttons. In addition, the color difference ΔE* of plastic buttons of nylon, acrylic, polyester, and casein dyed at the optimum operation conditions was evaluated by CIE L*a*b* theory.