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A series of five azo dyes derived from the diazonium salt of 4-aminoantipyrine and α- and β-naphthols and naphthalenediol were synthesized, and their chemical structures were identified by spectral measurements such as UV, FT-IR, and NMR, as well as elemental analysis. The chemical descriptor parameters of the synthesized dyes were computed using the B3LYP/6-31G(d,p) level. The dyes were classified as disperse dyes and were used to dye polyester fibers at high temperature and pH 4.0–5.0, utilizing acetic acid, while dispersing agents were added to enhance the stability and dispersion of the dyes. The color fastness properties of the dyed fibers were tested, and their color strength, reflectance, and dye exhaustion were measured. Finally, a plausible mechanism for the dyeing process was suggested. [ABSTRACT FROM AUTHOR]

Examination of natural quinone dyes and their dyeing properties exist in the literature. However, disperse dyeing of synthetic quinone dyes on textile materials and examination of these properties are quite rare. In this study, the derivatives of new N-,O-heteroatom-substituted-1,4-naphthoquinone dyes were synthesized with the reactions between 2,3-dichloro-1,4-naphthoquinone with some aromatic and aliphatic N-nucleophiles according to Michael addition mechanism and the exact structure of dyes were specified by using various spectroscopic methods (FT-IR, 1H NMR, 13C NMR, MS, and UV/Vis.) and microanalyses. In the second step of this work, the polyethylene terephthalate fabrics were dyed with these newly synthesized disperse dyes. Dyeing performances such as dye exhaustion (%), color, and color fastness (to washing, alkaline perspiration, acidic perspiration, water, seawater, wet rub, dry rub, sublimation, and light fastness) properties of these dyes on PET fiber fabrics were investigated and compared. The highest color yield (K/S) by 12.33 was obtained with dye compound 10 at a dyeing depth of 3% owf and displayed better dyeing performance than the other dyes studied. In conclusion, PET fibers dyed with dye 2-4-(4-Chlorofenoxyaniline)-3-chloro-1,4-naphthoquinone (dye compound 10) displayed the highest dye exhaustion (%) values, the highest color yields, and excellent washing, perspiration (alkaline and acidic), water and seawater and rub (dry and wet) fastness values with no staining whatsoever. [ABSTRACT FROM AUTHOR]

Decamethyl cyclopentasiloxane (D5) was devoted to the medium in the dyeing process of gardenia yellow on cotton fabric to improve the dyeing properties. The effects of D5 percentages and mordants, dyes dosage as well as dyeing temperature and time on dyeing properties were investigated. The results show that optimal dyeing processes of gardenia yellow on cotton in a siloxane-based medium are as follows: D5 percentages 94%vol, dye dosage 2% (o.w.f), alum as mordant dosage 3% (o.w.f), dyeing temperature 80 °C, dyeing time 40 min. Compared with water dyeing, cotton fabrics dyeing with D5/water present enhanced color strength (K/S value) and fine levelness. By fitting the dyeing curves, it is found that dyeing mechanism of gardenia yellow on cotton in D5 follows a pseudo-second-order kinetics model, which is alike to the dyeing kinetics in water. Owing to the hatred of D5, gardenia yellow is rapidly absorbed on the cotton fiber in initial dyeing process, then diffuses and reacts with cotton, which is drived by the diffusive force inducing by the concentration differences of dyes between dye liquor and fiber. In addition, the color fastness of cotton fabrics dyeing with D5/water is equal to that dyeing with water. This dyeing technique that immensely reduces dyeing wastewater has potential application in natural dyestuffs. [ABSTRACT FROM AUTHOR]

Abstract The use of natural bioresources in textile dyeing has attracted significant research interest due to their environmentally friendly and low-toxic nature. This study investigated the utilization of waste oyster shell (WOS) as a bio-mordant combined with sappan wood extract to dye silk fabrics using pre-, meta-, and post-mordanting method. The crystal structure of CaCO3 derived from WOS and their impact on color properties, color strength and color fastness were analyzed. The dyed fabrics displayed a range of shades from light pink to deep red and brown. FTIR analysis confirmed chemical interactions among dye, silk, and WOS mordants. Notably, silk treated with WOS at 800 °C as a pre-mordant showed color strength approximately 2.6 times higher than that of un-mordanted samples. Additionally, bio-mordanted samples exhibited improved color fastness compared to untreated ones (rating 2), with pre-mordanting offering the highest resistance to washing (rating 4–5). These findings shed light on the potential of waste oyster shell as an effective, sustainable alternative to conventional metal mordants in textile dyeing. This study not only support the utilization of waste but also enhances environmental and resource efficiency of the dyeing process.

Abstract The textile industry is witnessing a paradigm shift towards sustainable materials, prompting the exploration of novel natural fibers as alternatives to synthetic fibers to meet environmental standards and address the growing demand for eco-friendly and sustainable products. Different natural fibers possess varied properties and are suitable for numerous applications in conventional and technical textiles. The coloration of these textile materials is an important aspect of conventional textiles, which starts with the pretreatment of the material. This study introduces a novel blend of cotton and Bauhinia vahlii fiber, a lesser-known natural cellulosic fiber with promising textile properties, and evaluates its pretreatment outcomes and dyeability characteristics. The study employs a systematic approach to pretreat the cotton and Bauhinia vahlii fiber blend (cotton: Bauhinia vahlii fiber 70:30) in a single bath using a conventional combined scouring bleaching process. The pretreatment process is carried out two times with varied sodium hydroxide (NaOH) and hydrogen peroxide (H2O2) concentrations for different processing times at 90 °C to assess the component fibers’ whiteness index, union bleaching balance, and weight loss percentage under diverse pretreatment conditions. Each time, 50% of the chemicals were used and continued for half of the processing time. The dyeability of the treated fibers is analyzed by dyeing the same in a single bath using amron bright red HF2R bifunctional reactive dye in varied shade depths (1%, 3%, and 5%) and fiber blend ratios (cotton: Bauhinia vahlii fiber 100:0, 90:10, 80:20, 70:30, and 0:100) to assess the color strength, union dyeing balance, and fastness properties. The maximum whiteness was achieved with 6 g per liter (gpl) of NaOH and H2O2 and at a processing time of 150 min with a whiteness index of 80.46 and 54.34 of cotton and Bauhinia vahlii fiber, respectively, with a union bleaching balance of 1.48. The dyed fibers’ colorimetric results confirm that Bauhinia vahlii fiber gives higher color strength than cotton fiber, irrespective of shade depth and blend ratio. The union dyeing balance of 1.2 was achieved at 5% shade depth with a 70:30 cotton Bauhinia vahlii fiber blend. This research contributes to the conventional textile field by introducing a sustainable fiber blend that reduces reliance on synthetic fiber and opens new avenues for utilizing Bauhinia vahlii fiber in conventional textile manufacturing.

The textile industry is witnessing a paradigm shift towards sustainable materials, prompting the exploration of novel natural fibers as alternatives to synthetic fibers to meet environmental standards and address the growing demand for eco-friendly and sustainable products. Different natural fibers possess varied properties and are suitable for numerous applications in conventional and technical textiles. The coloration of these textile materials is an important aspect of conventional textiles, which starts with the pretreatment of the material. This study introduces a novel blend of cotton and Bauhinia vahlii fiber, a lesser-known natural cellulosic fiber with promising textile properties, and evaluates its pretreatment outcomes and dyeability characteristics. The study employs a systematic approach to pretreat the cotton and Bauhinia vahlii fiber blend (cotton: Bauhinia vahlii fiber 70:30) in a single bath using a conventional combined scouring bleaching process. The pretreatment process is carried out two times with varied sodium hydroxide (NaOH) and hydrogen peroxide (H2O2) concentrations for different processing times at 90 °C to assess the component fibers' whiteness index, union bleaching balance, and weight loss percentage under diverse pretreatment conditions. Each time, 50% of the chemicals were used and continued for half of the processing time. The dyeability of the treated fibers is analyzed by dyeing the same in a single bath using amron bright red HF2R bifunctional reactive dye in varied shade depths (1%, 3%, and 5%) and fiber blend ratios (cotton: Bauhinia vahlii fiber 100:0, 90:10, 80:20, 70:30, and 0:100) to assess the color strength, union dyeing balance, and fastness properties. The maximum whiteness was achieved with 6 g per liter (gpl) of NaOH and H2O2 and at a processing time of 150 min with a whiteness index of 80.46 and 54.34 of cotton and Bauhinia vahlii fiber, respectively, with a union bleaching balance of 1.48. The dyed fibers' colorimetric results confirm that Bauhinia vahlii fiber gives higher color strength than cotton fiber, irrespective of shade depth and blend ratio. The union dyeing balance of 1.2 was achieved at 5% shade depth with a 70:30 cotton Bauhinia vahlii fiber blend. This research contributes to the conventional textile field by introducing a sustainable fiber blend that reduces reliance on synthetic fiber and opens new avenues for utilizing Bauhinia vahlii fiber in conventional textile manufacturing. Highlights: The whiteness index of BVF increases significantly with an increase in NaOH and H2O2 concentration as well as processing time, and the maximum whiteness index is achieved with 6 gpl NaOH and H2O2 and a processing time of 150 min. The whiteness index of cotton and BVF is 80.46 and 54.34, respectively, with a union bleaching balance of 1.48 and a weighted average whiteness index of 72.62. In the case of cotton fiber, a weight loss of 5–7% is observed due to the pretreatment process, whereas a weight loss of 15–23% is observed in the case of BVF. Bauhinia vahlii fiber gives higher color strength than cotton fiber, irrespective of the shade depth as well as the blend ratio. The union dyeing balance decreases with an increase in shade depth. In 5% shade depth, it gives a union dyeing balance of 1.2 when dyed cotton BVF with a 70:30 blend ratio. [ABSTRACT FROM AUTHOR]

Spun-dyed lyocell fibers were prepared by mixing cellulose pulp with an indigo dye dispersion and subsequent spinning. The indigo dye dispersion was obtained by adding leuco indigo to N-methylmorpholine-N-oxide (NMMO) solution. The particle size of the indigo dye was controlled by adjusting the dispersion conditions. Furthermore, the application of ball milling resulted in a reduced average dye particle size of 222.3 nm. The structure and properties of the fibers were characterized using Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and strength testing. Indigo dye particles were distributed in the interior and surface of the fibers. Relative to the undyed fiber, the crystal structure of the colored fibers was unchanged, but the crystallinity and mechanical properties improved. The color strength and color fastness of the spun-dyed lyocell fibers were assessed according to industry standards. Increasing the dye content and reducing the dye particle size (via ball milling) increased the color strength of the fibers, and the color fastness to sun and soap washing was high (Gray card grade 5). Additionally, the dye did not diffuse into the spinning coagulation bath and thus did not affect the recovery of NMMO solvent. The present study demonstrates a viable strategy for preparing spun-dyed lyocell fibers. [ABSTRACT FROM AUTHOR]

The objective of this study was to establish a solvent-assisted salt-free dyeing method for cotton fabric utilizing commercially available reactive dyes. In this study, the feasibility of substituting water as the dyeing medium with environmentally friendly solvents, specifically ethanol (EtOH), isopropyl alcohol (IPA), and propanol (PrOH), was investigated. Eight commercial reactive dyes, each possessing distinct chemical structures, were examined with various dyeing characteristics including exhaustion, fixation, and fastness properties, in the presence of various alcohols. However, solvent-assisted dyeing exhibited comparable or enhanced color strength (K/S) values, exhaustion, and fixation rates compared to conventional aqueous dyeing. For instance, the RR35 dye demonstrated a substantial increase in K/S values with PrOH, EtOH, and IPA, ranging from 115 to 369% improvement. The substitution of alcohol for water did not affect the wash, rub, and light-color fastness properties, as these properties remained consistently excellent. Solvent-assisted salt-free dyeing of cotton fabrics offers a promising solution to address the environmental impacts of traditional water-based dyeing methods by eliminating the requirement for water and salt. Overall, this study presents a solvent-assisted salt-free dyeing technique and contributes to the field by offering detailed insights into its mechanisms and performance. Our research has the potential to reduce water consumption, eliminate salt usage, and mitigate environmental pollution. [ABSTRACT FROM AUTHOR]

Bamboo fiber is gaining the curious attention of researchers as well as the fashion and apparel industries as an alternative to the cotton fiber. Bamboo fabric besides having prodigious characteristics, possess several limitations i. e. high-cost, poor spin-ability, a significant reduction in strength under wet conditions etc. The present study is focused to address the problems associated with the bamboo fiber to make it user and environment-friendly. An isocyanate based compound, HDI (blocked hexamethylene diisocyanate) was chemically crosslinked with bamboo fabric to enhance its dyeability and fastness properties without compromising on its thermal stability and tensile strength. The dyeing properties, levelness, thermal stability, absorbency, and tensile and tear strength measurements of the HDI-based bamboo fabric were compared with the untreated fabrics. The HDI-based bamboo fabric dyed with commercial reactive dyes exhibited up to 10% and 9% increase in exhaustion and total percent fixation, respectively. Whereas the modified fabrics dyed with lab-synthesized reactive dyes displayed 12–14% and 10% increase in fixation and total percent fixation, respectively. Furthermore, the HDI-based bamboo fabrics possessed better dyeing levelness compared to the untreated fabrics. Light and rubbing fastness of some of the modified fabrics increased significantly. Absorbency of the treated bamboo fabrics decreased while no significant change in the thermal stability and tensile strength of the treated fabrics was noticed after HDI treatment. [ABSTRACT FROM AUTHOR]

Cotton fabric (CF) was coated with a new multifunctional flame-retardant system consisting of melamine phosphate (MP) and nickel (II) dimethylglyoxime (NDMG). The new coating was applied to enhance the flame retardancy, antibacterial activity, thermal stability, color strength, UV protection, and electrical properties of CF. The weight percentages of NDMG and MP that led to the maximum improvement in CF properties were identified. According to vertical and horizontal flammability tests, coating the fabric with 29%MP/1%NDMG prevented flame propagation in the samples. Moreover, it increased the limiting oxygen index (LOI) of CF from 17.9% to 36.9%. Thermogravimetric analysis (TGA) data presented that the MP/NDMG coating enhanced the char residue at 750°C. Antimicrobial investigations indicated that the coating 29%MP/1%NDMG reduced the growth of S. aureus and E. coli bacteria. UV shielding and color strength (K/S) results revealed that coated fabrics had excellent UV protection (UPF > 175) and enhanced K/S values. The tensile strength of CF was slightly decreased after the coating process. The dielectric constant (ε'), the dielectric loss (ε''), and AC electrical resistivity ( ρ A C ) with frequency (10-106 Hz) were also investigated. The electrical resistivity increased significantly after adding MP and NDMG to the CFs. The coated sample (23%MP/7%NDMG) showed the best dielectric properties, with a low dielectric constant of 2.6 and ρ A C of 1.40E+10 Ω.cm at 1000 Hz. [ABSTRACT FROM AUTHOR]

This study focuses on the improvement of the dyeability of cellulosic fibre with reactive dyes using a sustainable approach. A previously reported organic compound containing two epoxide rings, N1, N1'-(ethane-1,2-diyl) bis(N2-(oxiran-2-ylmethyl)ethane-1,2-diamine) (AXL-2) was employed as a cross-linker to the cotton fabric. AXL-2 was synthesized by reaction of epichlorohydrin (ECH) with triethylenetetramine (TETA). Reactive dyeing generates the most problematic effluent containing 20–50% dye in hydrolyzed form (due to the use of alkali in the dyeing process) along with large amounts of inorganic salts. Cotton fabric makes covalent interactions with AXL-2 that subsequently binds with the dye molecule containing free NH2 or OH groups in acidic conditions rendering efficient dyeing in the absence of alkali and salts. ESI-mass spectrometry and ATR–FTIR spectroscopy were used to characterize the synthesized compound, while the treated cotton fabric was characterized by ATR–FTIR and SEM–EDX. Dyeing properties of AXL-2 treated cotton fabrics were studied by measuring their K/S values, % exhaustion, % fixation, and % total fixation. Color difference between treated and untreated fabrics (DE) was evaluated using CIE lab system that exhibited excellent color depth on the AXL-2 treated cotton fabric compared to pristine cotton fabric. Color fastness properties of the dyed fabrics were also studied. No significant change in the absorbency and thermal stability of the fabric was noticed after treatment. The tensile strength of the treated cotton fabric before dyeing (TC) was reduced by 7.6% in warp and 3.5% in weft directions as compared to untreated cotton fabric (CC). However, the treated cotton fabric had lesser reduction in the strength warp-wise compared to untreated cotton fabric after dyeing along with an increase in the strength weft-wise. The novel dyeing method of treated cellulosic fibre by reactive dyes renders a sustainable and eco-friendly approach. [ABSTRACT FROM AUTHOR]

This study focuses on the sustainable utilization of Quinoa plant components, particularly its leaves, as a waste agricultural material for natural dyeing applications. Two distinct Quinoa genotypes, Titicaca and Giza, were selected for their natural dyeing properties. UV-VIS absorption spectra of Quinoa colorant extracts provided insights into their chemical composition, revealing distinctive peaks indicative of betalains (400–450 nm), chlorophyll (600–650 nm), carotenoids (400–500 nm), and aromatic amino acids (250–280 nm). Wool samples dyed with different plant parts such as flowers, leaves, and stalks exhibited distinct yellow hue, with leaves demonstrating the highest color strength. Metal mordants such as iron (II) sulphate, copper sulphate, and tin (II) chloride influenced color outcomes, highlighting their role in tailoring final appearance. Fastness properties of dyed wool samples were evaluated, with leaves showing moderate staining resistance and good light fastness. Additionally, antibacterial properties of leaves of Giza Quinoa variety were assessed, showing promising activity against Staphylococcus aureus. The antibacterial properties of fabrics dyed with the leaf extract by mordanting method with different metal salt mordants, particularly Fe, Cr, and Cu, exhibited significant enhancement. These results highlight the multifaceted benefits of Quinoa plant components in sustainable natural dyeing and textile applications, emphasizing their potential for eco-friendly practices in the textile industry.

The optimization of pretreatment parameters is one of the most important factors for the successful dyeing of textile materials. The aim of this study was to investigate the most effective way of pre-treating cellulose based lyocell knitted fabric in order to achieve an optimal result when dyeing it with reactive dyestuffs. This research investigates the effects of pretreatment by exhaust method on lyocell knitted fabric, which is analyzed using five different recipes. Pretreatment techniques that are being used are mild pretreatment, hot wash without detergent, hot wash with detergent, causticization, and hot wash with causticization. Pretreated and untreated lyocell fabric is dyed with bi-functional reactive dyestuffs in a shade of 1%, to produce color. Three key factors are considered in this research work: optimum pretreatment technique, causticization time selection, and causticization concentration selection. In order to optimize the pretreatment technique, 16 trials are performed by varying the time and concentration. Compared to other pretreatment techniques, causticization is the best for dyeing lyocell fabric with reactive dyes. Additionally, causticization treatment is observed to have the best performance on lyocell fabric when applied for 30 min. The optimum concentration of NaOH for causticizing lyocell fabric is 3 mol/l, as determined by the results. This assessment of results is done based on four factors such as K/S value (color strength), strength loss %, weight loss % as well as pilling test results. [ABSTRACT FROM AUTHOR]

This research work investigates the chemical modification of cotton cellulose with a cationizing agent (CHPTAC, 3- chloro-2-hydroxylpropyl trimethyl ammonium chloride), which resulted in the enhanced dye uptake and increased color strength (K/S) on the dyed cotton fabric in the absence costly auxiliaries, such as sodium chloride and sodium hydroxide. The modified and unmodified cotton fabric samples were dyed using the exhaust dyeing method on a hightemperature dyeing machine with several reactive dyes of the Remazol class in different shade depths. The dyed samples were washed, dried and tested for K/S and colorfastness properties (washing, rubbing, and light), using standard test protocols. The results revealed that the color strength and the colorfastness properties of the modified dyed cotton fabric were significantly better than those of unmodified cotton. Thus, this study attempted a sustainable approach in cotton dyeing without using salt and alkali. [ABSTRACT FROM AUTHOR]

Polyimide (PI) fiber, as a high-performance fiber, possesses advantageous properties, such as outstanding thermal stability, fire resistance, and chemical resistance. It has great potential for use in warm clothing in extremely cold environments and fire-protective textiles, but has poor dyeability. In the present work, PI fiber was pretreated by ammonia and then dyed. The result shows PI fiber could be dyed with basic dyes after the assistance of ammonia. The X-ray diffraction analysis displayed an apparent change in the crystallinity of polyimide fibers. The thermogravimetry analysis illustrated that ammonia penetrated into polyimide fibers, but ammonia pretreatment had an insignificant effect on thermal stability. These changes in polyimide fibers indicated that ammonia could combine with the fiber macromolecules, penetrate inside fibers, and swell the fibers, resulting in elongation of polyimide fiber and decrease in the breaking force. The treated sample had higher color strength than the untreated sample did. The study of dyeing mechanism of PI fibers demonstrates that the Nernst adsorption isotherm is a favorable model for polyimide fiber dyeing with basic dyes. [ABSTRACT FROM AUTHOR]

A million ton of cotton fabric is wasted during cutting process in garment industry as well as in textile dyeing industry due to faulty dyeing. Color stripping of cotton fabric has become a significant challenge in the textile industry because the harsh chemicals used in chemical stripping processes affects the quality of fabric very badly. Conventional stripping methods lead with severe effects due to prolonged treatment time and high chemical concentrations. Recently, microwave-assisted stripping techniques have been emerged as effective alternatives to improve stripping efficiency. In this research, the developed microwave assisted stripping system is improved by the application of Urea, which is utilized as a microwave absorber to further reduce stripping time, temperature, and chemical concentration kept focus on quality parameters of recycled cotton fabric. This study inspects the efficiency of microwave absorber-assisted alkali hydrolysis and reduction in terms of dye-fabric bond cleavage, chromophores removal, chemical consumption, and processing time and compared with sequential stripping, microwave assisted stripping without absorber and conventional methods. The results indicated that microwave absorber-assisted alkali hydrolysis and reduction achieved 90 % stripping efficiency by using lowest concentrations of chemicals, while sequential stripping yielded a stripping efficiency of 96 %. Similarly, microwave absorber assisted methods resulted in minor loss in tear strength and weight. These outputs highlight the superior performance of microwave absorber-assisted techniques, demonstrating their efficiency, novelty, time-saving nature, and reduced damage compared to other methods.

The white fabric was printed with different printing temperatures and pressing times using the sublimation printing process in solid-tone black color with a 100 % total ink limiting level. Non-uniformity of the print was examined through print mottle determined by grey level co-occurrence matrix (GLCM) image processing method. Color strength of print was also determined by reflectance spectrophotometry. The print with the lower print mottle was obtained at a printing temperature of 190 °C at a longer pressing time of 120 s or at an increased printing temperature of up to 210 °C at the reduced pressing time of 60 s. The print with the lower print mottle had the lowest entropy, contrast, and correlation and the highest energy and homogeneity. The print with a higher color strength was accompanied by decreased print mottle. Choosing a suitable printing temperature and pressing time for sublimation printing is helpful in achieving print with low print mottle and high color strength and balancing cost, price, and price.

In response to the heightened awareness of infectious diseases and the growing emphasis on personal protection in daily life, the utilization of natural bioresources for textile fabric dyeing has garnered substantial research attention. This is particularly due to their ability to confer antibacterial and UV protection properties to fabrics. In this study, the dyeing properties of Mimusops elengi Linn extract, alone and mordanted, were evaluated on blended wool/acrylic and silk fabrics, along with an assessment of their antibacterial and UV protection characteristics. The dyed fabrics exhibited good color strength and color fastness. Quantitative assessment of antibacterial activity was conducted using the reduction percentage test, while UV protection properties were determined through the measurement of Ultraviolet Protection Factor (UPF). Aqueous extract alone, when applied to blended wool/acrylic fabric, demonstrated an impressive 99.88 % reduction against Staphylococcus aureus, and 48.33 % for silk fabric, albeit less effective against Escherichia coli. Notably, when fabrics were dyed with a combination of leaves extract and various metal salt mordants, a substantial improvement in antibacterial properties was observed. Zinc and copper salts, in particular, exhibited the ability to enhance antibacterial properties to almost 100 % against Staphylococcus aureus and Escherichia coli in both blended wool/acrylic and silk fabrics. Concurrently, this combination contributed to an increase in the UV protection property of both fabrics. The findings underscore the potential of plant-based natural dye for blended wool/acrylic and silk fabrics, imparting antimicrobial and UV protection properties. This has significant implications in preventing the spread of infections and skin diseases, emphasizing the vital role of such textiles in promoting health and well-being.

This research focuses on the use of tannin components in tamarind seed coats as a mordant and natural dye in cotton fabrics. Tannins were extracted from the tamarind seed coat by boiling method and then the tannin content was determined. The tannin extract was then used as a natural mordant with the addition of metallic copper sulfate (CuSO4) mordant. Tannin extract is also used as a dye on fabrics with the addition of sodium sulfate (NaSO4). The color strength of the tannins in the fabric was analyzed using a spectrophotometer from the rinse water. The results showed that the cloth that had been given the mordant had a stronger color strength than the cloth without the mordant. The use of mordant was varied at concentrations of 5, 10, 15, 20, and 25%-owf. The results of the analysis showed the most optimum tannin concentration at 15%-owf. The concentration of tannin used in the coloring process was also varied at concentrations of 5, 10, 15, 20, and 25%-owf. The results of the analysis show that the concentration of tannin used in the dye does not affect the strength of the color, but only affects the brightness of this color.

Todays, there is a strong tendency toward eco-dyeing with natural products. Several natural dyes have been used for dyeing protein fibers such as wool and silk fiber. This work examines the effect of metal mordant and biomordant on the color strength of dyed woolen yarn with madder, weld, and pomegranate natural dyes. The wool was mordanted with alum metallic and colorless mordant as well as walnut as colored and biomordant in pre-mordanting method. The madder, weld, and pomegranate natural dyes were extracted via ultrasound-assisted extraction (UAE). The woolen yarn was dyed with concentrations of 10, 20, 30, 40, 50, 60, 70, 80, 90, and 100% WOF of natural dyes. The absorption behavior and dyeing properties of natural dyes were explored by measuring the reflectance spectra and colorimetric parameter of dyed samples. The spectral derivative method was used to analyze the reflectance spectra. The color strength of natural dyes was evaluated by measuring the K/S as reflectance function at λ max (SWL), SUM, WSUM, FK, KSgm, KSf, SKSf, and the first-order derivative of K/S spectra. The colorimetric study indicated that the color of the dyed woolen yarn changed with alteration of the mordant. The statistical analysis revealed that there were significant correlations between the first-order derivative of K/S spectra d1(K/S) as a new color strength parameter and other color strength parameters such as SWL, SUM, WSUM, KSf, SKSf, and color strength parameters. The obtained results indicated that the color strength of the natural dye with alum as metal mordant was greater than that of walnut as colored and biomordant. The study of fastness properties of dyed samples with madder and weld natural dyes showed that the wash and light fastness of the sample with alum mordant were better than those of walnut mordant. However, the samples dyed with pomegranate natural dye indicated that the wash and light fastness were the same for alum and walnut mordants. [ABSTRACT FROM AUTHOR]

This study optimized the salt free reactive dyeing process using the Taguchi approach. Dyeing of cotton fabric with reactive dyes is popular because of its bright and brilliant color in various shade ranges. Cationization with ALBAFIX-WFF and the dyeing process on cotton fabric was carried out using the exhaust method. To determine the optimum process conditions, two types of multiple characteristic parameters, including the single characteristic value conversion method and the process maximization method, were used on the basis of color strength (K/S) and wash fastness. The single characteristic value conversion method confirmed that the optimum process condition was a cationization temperature of 40 °C and a dyeing pH of 11. Most importantly, the optimal conditions were confirmed by the process maximization method as a concentration of ALBAFIX-WFF 30 g/L, cationization temperature at 80 °C, dyeing pH 12, and material-to-liquor ratio (M:L) of 1:5. More suitable dyeing properties are also achieved by the process maximization method.

In this study, we report on a sustainable, pure okra woven fabric made of 100% okra fiber and its physical, mechanical and dyeing behaviors. To ensure the feasibility of industrial applications, the fabric attributes have been compared with a similar construction of jute fabric which has worldwide commercial applications. Experimental results revealed that the tensile strength of okra and jute woven fabric was respectively 815.2 N and 918.893 N in the warp direction and 621.047 N and 658.2 N in the weft direction. Nevertheless, okra woven fabric outperformed jute fabric in elongation, with 16.34 and 8.449% in the warp direction and 11.856 and 7.342% in the weft direction, respectively. Okra fabric demonstrated greater tear strength, high stiffness and more abrasion resistant than jute one, while jute fabric presented more shrinkage than okra. The one-way analysis of variance (ANOVA) data of the mechanical properties of the woven fabrics displayed a significant variance in the tear strength, flexural rigidity, and shrinkage. Both fabrics have undergone alkali and enzyme treatments before dyeing. Compared to an alkali-treated fabric, the dyed one with enzyme treatment had stronger color retention properties. Both the colored fabrics exhibited improved color fastness properties, receiving Grade 3 in dry and wet conditions. Identical Fourier transform infrared (FTIR) spectra was found for similar treated colored fabrics of okra and jute. With this comparison, it can be stated that appropriate usage of available natural resources and environmental agro-wastes become vital materials for establishing sustainability and productivity in commerce. [ABSTRACT FROM AUTHOR]

This study optimized the salt free reactive dyeing process using the Taguchi approach. Dyeing of cotton fabric with reactive dyes is popular because of its bright and brilliant color in various shade ranges. Cationization with ALBAFIX-WFF and the dyeing process on cotton fabric was carried out using the exhaust method. To determine the optimum process conditions, two types of multiple characteristic parameters, including the single characteristic value conversion method and the process maximization method, were used on the basis of color strength (K/S) and wash fastness. The single characteristic value conversion method confirmed that the optimum process condition was a cationization temperature of 40 °C and a dyeing pH of 11. Most importantly, the optimal conditions were confirmed by the process maximization method as a concentration of ALBAFIX-WFF 30 g/L, cationization temperature at 80 °C, dyeing pH 12, and material-to-liquor ratio (M:L) of 1:5. More suitable dyeing properties are also achieved by the process maximization method. [ABSTRACT FROM AUTHOR]

The white fabric was printed with different printing temperatures and pressing times using the sublimation printing process in solid-tone black color with a 100 % total ink limiting level. Non-uniformity of the print was examined through print mottle determined by grey level co-occurrence matrix (GLCM) image processing method. The color strength of the print was also determined by reflectance spectrophotometry. The print with the lower print mottle was obtained at a printing temperature of 190 °C at a longer pressing time of 120 s or at an increased printing temperature of up to 210 °C at the reduced pressing time of 60 s. The print with the lower print mottle had the lowest entropy, contrast, correlation and the highest energy and homogeneity. The print with a higher color strength was accompanied by decreased print mottle. Choosing a suitable printing temperature and pressing time for sublimation printing is helpful in achieving print with low print mottle and high color strength and balancing cost, price, and price. [ABSTRACT FROM AUTHOR]

This study explores the application of 3-chloro-2-hydroxypropyl trimethyl ammonium chloride as a cationizing agent to modify viscose rayon fabric by the pad-batch method. This modification overcomes the electrostatic repulsion between negatively charged cellulose and acid dyes during dyeing, enabling dyeing without the need for electrolytes. Thus the dyeing of the cationized viscose rayon fabric is achieved with the negatively charged acid dyes without any electrolyte. The dyeing properties of unmodified and modified fabric samples with three different acid dyes (Lanasyn Orange NLI, Brillion Brill Red MF/3B 140, and Nyloson Navy NRBL 220) with the shade depths as 1%, 2%, 4%, and 6% owf by exhaust method are examined. The results indicate that modified viscose rayon fabric offers significant color yield values and improved fastness properties such as washing, light, perspiration, and rubbing. The novelty of this research lies in the ability to dye cellulosic fibers such as viscose in this case with acid dyes, while originally these dyes are typically used to color polyamide fibers. [ABSTRACT FROM AUTHOR]

The extraction of natural dye using an aqueous method is a concept of green chemistry to avoid environmental pollution and toxicity. The present study was performed to improve the color strength and fastness properties of the fabrics by using natural dye and banana pseudo stem sap as a natural mordant. The natural dye was extracted from marigold flowers (Tagetes erecta) and optimized for dyeing of cotton and silk fabrics. The extraction of the dye was done in an aqueous solution without using any solvents. The optimum results were obtained when the fabric was dyed at 80°C for 60 min by keeping the mass to liquid ratio 1:40 at pH-7 (1.19). The color strength and CIELab (L*, a*, and b*) color parameters were also investigated. The effect of banana pseudo stem saps as a natural mordant on the color strength and fastness properties of the cotton and silk fabrics were evaluated and compared. The cotton fabrics were further characterized by FTIR spectroscopy and Scanning electron microscopy (SEM) to assess the physical and chemical changes after dyeing and mordanting.

Reaktif boyarmaddeler pamuğun boyanmasında en yaygın kullanılan boyarmaddelerdir. Pamuklu kumaşların reaktif boyanması için yüksek miktarda kullanılan elektrolit kaçınılmaz olarak çevresel tehditler oluşturmaktadır. Kitosan üstün özelliklerinden dolayı tekstilde birçok alanda farklı amaçlarla kullanılmaktadır. Bu çalışmada, sentetik polielektrolit poli(akrilik asidin sodyum tuzu) reaktif boyamada inorganik elektrolit sodyum klorür yerine kullanımı ve kitosanın kumaşın reaktif boyama davranışı üzerindeki etkileri araştırılmıştır. Ayrıca kumaşların yıkama haslıkları ve ultraviyole koruma faktörleri de gözlemlenmiştir. Boyamadan önce kitosan ile muamele ve boyamada sodyum klorür kullanımı konvansiyonel boyamalara göre renk derinliklerini arttırmış ve bu artış kitosan konsantrasyonundaki artışla devam etmiştir. Öyle ki, %8 konsantrasyonda kitosan uygulamasını takiben %2 konsantrasyonda yapılan boyamadan, %3 konvansiyonel boyamanın renk kuvvetine benzer değerler elde edilmiştir. Sodyum klorür konsantrasyon artışının renk derinliği üzerindeki etkisi polielektrolitten daha belirgin olarak gözlemlenmiştir. Poli (akrilik asidin sodyum tuzunun) pamuğun reaktif boyamasındaki çalışma prensibinin iyonlaşamaması, sıcaklık-konsantrasyon-pH duyarlılığı ve hidrofobik boya kombinasyonları oluşturması nedeniyle nispeten karmaşık olduğu anlaşılmıştır. Ayrıca boyarmaddelerin farklı tuz duyarlılıklarının da elektrolitlerin etkisinde farklılık yaratmış olabileceği düşünülmüştür. Kitosan aplike edilen ve boyanan numunelerin yıkama haslıkları iyi-mükemmel seviyede iken, kitosan aplikasyonunda kullanılan çapraz bağlayıcının bu değerleri 0,5 puan kadar artırdığı görülmüştür. Boyarmaddelerin ultraviyole koruma faktörünü arttırmada kitosandan daha etkili olduğu gözlemlenmiştir.

In this research work, cotton fabrics were dyed through Senegalia Catechu dye in two different mordants conditions such as myrobalan and pomegranate rind power. Three process parameters were taken, such as dyeing temperature, dye bath pH, and mordant concentration for optimization, and other processing conditions were kept unchanged. The Box-Behnken-L15 experimental design was followed for experimentation. Regression models were generated for two different mordanting conditions, and their statistical significance was also verified through ANOVA. A comparative analysis between two mordant conditions was done through RSM analysis and found that shade variations between the two different mordanted samples were noticeable in most cases. The FTIR and SEM analysis on the dyed fabric was carried out to understand the dyeing effectiveness and chemical modification of the structure. The optimized process parameters of myrobalan mordant condition are pH level (6–7), maximum dyeing temperature (80°C), and maximum mordant concentration (25%-30%). The optimized process parameters of pomegranate rind power are pH level (9–10), moderate dyeing temperature (70°C), and maximum mordant concentration (25%-30%). These differences were interpreted due to the chemical nature of mordants, dyeing condition, raw material specification etc.

Chemical modification is a promising path to address the limitations of a natural dye, such as limited shades and inadequate fastness properties. This study investigated the modification of embelin (2, 5-dihydroxy-3-undecyl-1, 4-benzoquinone) a plant-based benzoquinone compound from Embelia schimperi (Myrisinaceae family) with ninhydrin to get a semi-synthetic dye. The modified dye was applied to cotton fabric along with mordants to provide different shades. Optimum dyeing conditions were determined using Central Composite Design which showed optimum conditions of pH at 9, time of 60 min and temp of 80°C. The color fastness ratings were in the range of 4–5 evaluated on the Gray scale.

The objective of this research was to use the hydrogen peroxide as eco-friendly washing product to achieve a fading effect by creating a desirable gray vintage-look on sulfur black-dyed jean fabric. Visual appearance and colorimetric study using spectrophotometer showed that only the new two-steps process developed in this study helps to get the desirable look appearance with a good fastness. The (K/S)sum value of the two-steps process washed fabric decreased significantly (23.9% and 38.1% for washing at 80°C and 95°C, respectively). The SEM photos indicated that the physical properties of the cotton fibers are changed by effect of the peroxide hydrogen washing two-steps process. Indeed, a part of the cuticle is removed and the natural twists is disappeared with a specific tendency to fibrillation causing roughness and chemical heterogeneity of the fabric surface. The surface wettability of the two-steps process washed fabric was deeply changed as estimated by the initial contact angle values, the droplet spreading, the absorbency kinetics, and the total processing time of spreading.

The study approached to extract natural dye from the wastage leaves of Polyalthia longifolia and evaluate the dyeing properties on silk and cotton fabrics. Different analysis techniques were used to understand the characteristics of the dye and apply them to silk and cotton fabrics using UV–Vis spectrophotometer, FTIR, and SEM. The colorimetric properties were analyzed by reflectance spectrometry in terms of L*, a*, b*, c*, h°, and K/S values. The color fastness was investigated in terms of light, wash, rub (dry/wet), and perspiration tests. The optimum dye extraction obtained was 18% at 90°C in 60 min of extraction in the aqueous alkaline medium. The analysis results showed that the extracted reddish-brown colored dyes confirmed the presence of tannins and phenolic compounds. The color was fixed firmly on silk fabrics without any mordant. The post-mordanting method with ferrous sulfate and copper sulfate showed a better shade and lightfastness than other mordanting processes on silk fabrics. Ferrous sulfate and copper sulfate mordanted cotton fabrics showed good light and wash fastness properties. The study observed that the extracted natural dye of P. longifolia has the potential to be used as a textile dye.

The innovation anticipated here is the use of our previously prepared chitosan nanoparticles in conjunction with citric acid and sodium hypophosphite for rendering viscose fabrics dyed and finished concurrently in one step with dual classes of dyes, namely basic and acid dyes, using a pad-dry-cure process. This was done to see the effect of the aforementioned eco-friendly finishing formulation on creating dual anchoring sites onto finished fabrics for dye-ability using Basic Red 2 and Acid Orange 7, which have no direct affinity to viscose fabric. So, different concentrations of CA, CNPs, and dyes were mixed into a viscose fabric cross-linking formulation together with a set concentration of SHP (50% based on weight of CA concentration) and cured at 170°C for 2 minutes. Citric acid is predicted to react with the hydroxyl groups in viscose and CNPs to produce ester crosslinking and/or to form an inter-ionic attraction with the amino groups of CNPs. The latter was responsible for viscose fabrics dye ability with Basic Red 2 by anchoring the free carboxyl groups in citric acid, as well as their dye ability with Acid Orange 7 by anchoring the residual amine groups in CNPs.

The increasing awareness of toxicity of synthetic dyes has considerably raised the demand for natural dyes. Retaining color fastness and strength of natural dyes on fabric is the main limitation in textile dyeing with natural dyes. In this study cotton fabric was pre-treated with aqueous tannic acid in order to enhance the fabric’s color fastness and strength of the natural dye. The untreated, treated and dyed cotton were characterized using Fourier-Transform Infrared spectroscopic analysis to confirm the modification of the cellulosic fiber. Different solvents were used to extract dye from Erythrina abyssinica plant and subjected to phytochemical quantification then used to dye cotton. The new FTIR peaks at 2646 cm−1and 1578 cm−1, which correspond to carbonyl (C=O) stretching mode and C=C stretching mode for aromatic ring, respectively, confirmed the modification and dyeing due to the attachment of the aromatic dye molecules to the cellulose structure. It was noted that modification of cellulose structure enhanced color strength and fastness. Mordanting with alum and ferrous sulfate using different methods formed variety of shades that ranged between light yellow to greenish yellow. Therefore, Erythrina abyssinica plant can be used as a source of natural dye for dyeing cotton fabric.

The new technologies and materials necessary for the development of antibacterial fabrics have been of great interest to researchers in recent years. This study focuses on the investigation of the natural waste product such as onion peel-based nanoemulsion for dyeing of cotton and cotton blended fabric samples. 100% cotton and polyester/cotton fabrics have been dyed with two different concentrations (5% and 10%) of onion peel (OP) extract-based nanoemulsion (NE). Antibacterial activity of dyed samples has been tested against both the Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative) bacteria. Among all the fabric samples, the 100% cotton fabric dyed with 10% onion peel-based nanoemulsion (OP-NE) registers the highest antibacterial activity of 75 and 57% against S. aureus and E. coli, respectively. However, the antibacterial effectiveness remained substantial at 38 and 31%, respectively, even after 25 home laundry washes. The test specimens have been further tested for their color strength, ultra-violet protection factor (UPF), tensile, and tear strength properties to evaluate the change in their physical properties.

In recent years, natural dyes are gaining importance in textile dyeing applications as they are renewable and biodegradable. In the present study, we selected Eleutherine bulbosa bulbs as a source of natural colorant for dyeing cotton fabrics. Water was used for the extraction of dye, a step toward eco-friendly dyeing. The dyeing was carried out with different mordants and color fastness properties were determined. Relatively higher color strength values were obtained with Myrobalan fruit extract (Mfe- 4.267) and Pomegranate rind extract (Pre- 2.731) as mordants. With Mfe and Pre good color strength values were retained even after detergent wash (3.103 and 1.865) or light exposure (3.689 and 2.395). A combination of Eleutherine dye with turmeric extract was also experimented. Results showed better color strength values with Mfe (4.304) and Pre (3.120). The color retainability after detergent wash (2.960 and 2.100) or light exposure (4.186 and 2.911) was also good with these mordants. Results revealed that E. bulbosa could be used as a source of an ecofriendly dye for cotton fabrics, and the dye-fixing is most effective with the natural mordant myrobalan. The composition of dye extract was analyzed by LCMS technique, 15 compounds were detected, most of which are quinone derivatives.

The purpose of this study is to propose a fully sustainable dyeing process for nylon 6. In order to achieve this goal, Rhubarb flower parts were used to produce a brown hue on nylon 6 fabric. The effects of dyeing parameters such as dyeing time, temperature, dyebath pH, M:L, salt addition, dispersing agent, and dye concentration on color strength were investigated. Using 100%owf dye in an acidic medium at boil and the material to liquor ratio of 1:30 for 75 min was determined to be the optimal condition for dyeing nylon 6 with rhubarb flower. In order to achieve acceptable color fastness, four natural mordants were applied, including walnut husks, pistachio hulls, pine cones, and green coffee. Colorimetric measurements revealed that mordanting did not affect the hue of the color compared to the non-mordant sample. In addition, diverse natural mordants produced the same color (i.e., brown) with varying color strengths, of which 10%owf walnut husk generated the strongest color. Bio-mordanted samples were also found to have excellent color fastness, thereby providing an effective substitute for metal mordants. [ABSTRACT FROM AUTHOR]

Spent coffee grounds (SCGs) are commonly known as a waste resource and a raw material useful for dyeing. SCG is a rich source of natural colorant from the class of flavonoids and anthocyanins. In this research, silk fiber dyeing with the dye which was extracted from SCGs with different metallic and natural mordants was done by applying pre-, meta-, and post-mordanting methods. Metal salts like tin chloride and copper sulfate as well as such natural materials as pinecone, tannic acid, and lemon peel were used to act as mordants. Color strength and color parameters of the dyed silk fabric samples were evaluated by applying a reflective spectrophotometer. Also, the evaluation of wash and light fastness was done based on ISO standards. The results indicated that in all methods, the metal samples had higher color strength when compared to the bio-mordant ones. Among the used methods and bio-mordants, the use of the pre-mordanting method and pinecone led to the highest amount of color strength. Also, the used bio-mordant could be a suitable substitute for metal mordants in terms of fastness parameters. Among the used methods and mordants, the post-mordanting method and pinecone mordant could provide the best washing and light fastness. [ABSTRACT FROM AUTHOR]

The enormous number of pineapple plantations in Malaysia are dominated by small to large agronomists governed by the Malaysian Pineapple Industrial Board, which addresses almost all pineapple industry-related issues. In Malaysia, more than 147,000 hectares of land are utilized for pineapple plantations, which create 65 tons of residue per hectare. Consequently, the waste production comes from the long leaves of the harvested mother plants of pineapples that are cut off to allow the young sucker to grow freely, which then can be found abundantly. However, the handling practice for pineapple leaf waste in Malaysia is still poorly managed. Realizing the importance of this issue, as an alternative to reduce waste, fibers from pineapple leaves were extracted and dyed to improve the aesthetic value and marketability of pineapple leaf fiber by adding dyeing substrates using a low energy consumption dyeing approach. Two different techniques of dyeing were used to investigate the morphological, mechanical, color strength, and colorfastness properties of dyed pineapple leaf fibers. The dyeing of pineapple leaf fibers was investigated using C.I. reactive blue 5, C.I reactive red 11, and C.I Reactive yellow 86 at different concentrations. As a result, the characterization of dyed pineapple leaf fiber (PALF) showed that the dyeing process modified the original structure of PALF but no significant differences were observed on dyed PALF in the comparison of each dyeing technique. In addition, under optimized conditions of two dyeing techniques dyed PALF presented lower breaking strength, whereas comparable breaking strength value was gained with each technique. Fibers of both dyeing techniques displayed interesting color findings with excellent colorfastness to washing, lightfastness, and good colorfastness to perspiration. The infrared dyeing method resulted in similar and better dyeing behavior compared to exhaustion dyeing techniques. This method could further be refined by considering the production of textile materials, which can provide alternative to the usage of highly expensive silk fibers in the songket making industry. [ABSTRACT FROM AUTHOR]

Color stripping is a primary technique for recycling fabric. In view of cost, time and energy effectiveness in present research, microwave assisted sequential stripping of cotton with fixed Reactive Blue Black 5 and Turquoise CLB was developed as an alternate method to conventional stripping. After microwave assisted alkali → oxidation → reduction treatment, 98% and 97% stripping efficiency was obtained in 120 s, for reactive blue black 5 and reactive turquoise CLB respectively. Similarly, 97% and 94% stripping efficiency was calculated by sequential acid → oxidation → reduction in 120 s, while similar results were obtained by conventional methods in 60 min. However, a minor discrepancy in terms of weight loss and tearing strength was also observed in the sequential microwave assisted methods in comparison to conventional methods. Assessment of redyeability of stripped cotton fabric against all in-vogue methods proved microwave assisted method to be a better commercial option than any other one for stripped fabric quality, time, energy and cost effectiveness. [ABSTRACT FROM AUTHOR]

The present study aims at optimization of dyeing process parameters such as dyeing temperature, dyeing pH, and mordant concentration toward achieving maximum color strength and antimicrobial activity of cotton fabric dyed with Indian madder (Rubia cordifolia) as a natural dye. Box-Behnken three factorial with three levels experimental design (dyeing temperature ranges are 60ºC, 70ºC, and 80ºC, dyeing pH ranges are 6, 9, and 12, Mordant concentration ranges are 10%, 20%, and 30% of OWF) was used for optimization. Results showed that all the selected process variables have influenced the color strength as well as antimicrobial activity against the microbes such as Staphylococcus aureus and Escherichia coli. The quadratic regression models have been developed for optimization of all the process parameters and it was validated through ANOVA. UV-Vis spectroscopy, Phytochemical analysis, and FTIR studies have been conducted to confirm the presence of the phytochemical compounds.

Black rice is known as a health-promoting food for its abundant content of anthocyanins. The main objective of this paper is to get functional and eco-friendly materials dyed with black rice extract. In this research work, chitosan-modified cotton fabric was dyed with the black rice extract, and the fabric’s CIELab color characteristic values (L*, a*, b*, C*), color strength (K/S) value, and UPF value were investigated closely. The K/S value and UPF value of dyed samples depend on temperature, time, and pH. It is worth noting that the acid medium favored the dyeing to obtain a purple-red color and achieve a larger K/S value and UPF value. The results showed that chitosan-modified cotton fabric dyed with black rice extract had good UV resistance and color fastness.

The main purpose of this study is to develop a green dyeing process using Corchorus olitorius dye extract. Corchorus olitorius leaves were used as a new dyestuff source that has never been used for cotton fabric dyeing. Dye extraction was performed using a non-conventional clean process containing ethanol in an ultrasound bath. The extracted dye was applied to cotton fabric in a bath exhaustion process. The effect of dyeing parameters on the color strength of dyed fabric was studied. A response surface methodology design was used to optimize the dyeing process. The results showed that pH, dyeing temperature, and dyeing time significantly affect the dyed fabric. The optimum dyeing parameters were found at 90°C in a bath pH of 9 for 90 min. Finally, to improve the color strength, and the color-fastness, three mordanting processes, and three different mordants were used. Results show that pre-mordanted dyed cotton fabric using aluminum potassium sulfate produces the best fastness properties.

For the current study, Bougainvillea flowers as environment friendly sustainable source of plant-based natural dye have been selected as an alternative to toxic synthetic dyes for dyeing of cotton and silk. Natural colorant from Bougainvillea flowers (Bougainvillea glabra) was extracted using aqueous and acidic extraction media. Maximum colorant was extracted in aqueous medium, and further it was used for cotton and silk dyeing. The optimum values of the dyeing parameters including dyeing time, dye to liquor ratio and salt level as exhausting agent were found to be 30 min, 35-mL liquor ratio and 3.0 g for cotton and for silk 45 min dyeing time, 45-mL liquor ratio and 3.0 g exhausting agent in aqueous dye extract. Bio mordanting has been applied to attain a variety of color shades. The utilization of 3% of henna, 4% of turmeric for silk pre-mordanting and for post-mordanting turmeric at 3% and henna at 4% for silk gave a darker shade. For cotton bio mordanting, 2% turmeric rhizome powder, 3% henna leaves powder extract as pre-mordant and 2% turmeric, 3% henna as post-mordant has developed a variety of shade. Overall, it has been found that natural colorant from Bougainvillea flowers is the new dye source for bio-coloration of natural fabrics, and addition of bio mordants has made the process more calming and eco-friendly. [ABSTRACT FROM AUTHOR]

Basic Brown 16 pigment and three types of surfactants were used to prepare the cationic, nonionic, and anionic basic hair dyes. White hair and bleached hair were dyed using the three basic hair dyes and were shampooed 10 times using acidic, neutral, and alkaline shampoos prepared in the study. White hair and bleached hair dyed with the anionic basic hair dye resulted in a lower L*, a*, b* values and lower K/S values compared to the hair dyed with the cationic and nonionic basic hair dyes and the results were statistically significant at α = 0.05. Hair dyed with the anionic basic hair dye showed significantly higher ΔL*, Δa*, Δb*, and ΔE*ab values after 10 times of shampooing than those dyed with cationic and nonionic basic hair dyes (α = 0.05), indicating a lower color resistance for the anionic basic hair dye. Color difference after shampooing was significantly higher when alkaline shampoo was used (α = 0.05). Overall, the color difference after shampooing occurred more by the type of dye than by the type of shampoo. [ABSTRACT FROM AUTHOR]