Eco-friendly dyeing of poly(trimethylene terephthalate) with temporarily solubilized azo disperse dyes based on pyridone derivatives

Dispersant-free PTT dyeing of temporarily solubilized azo disperse dyes based on pyridone moiety which contain β-sulfatoethylsulfonyl group was investigated. The dyes were successfully applied to PTT without the use of dispersants. The color yields of the dyes on PTT fabric were dependent on dyeing pH as well as dyeing temperature. The optimum results were obtained at pH 5–6 and 110 °C. The dyes showed alkali-clearing property and exhibited good to excellent fastness on the PTT fabric. The COD levels of the dyeing effluent from the temporarily solubilized disperse dyes were much smaller than those from commercial disperse dye.     

Efficient separation and reuse of CI Reactive Blue 19 from dyeing effluent by solvent extraction

In order to reduce environmental pollution from dyeing effluent, the cationic reverse micelles were prepared and used for removal of anionic Color Index (CI) Reactive Blue 19. The effect of surfactants, dyes, temperature and ultrasonic treatment on dye removal was investigated, respectively. The conductivity of CI Reactive Blue 19 aqueous solution was measured during removal process. In addition, the photograph of CI Reactive Blue 19 was also obtained. Finally, the removed dyes were backward extracted and reused for dyeing cotton fabrics. The results indicated that the removal of dyes was increased with increasing surfactants concentration and temperature, while the dye concentration exhibited the reverse trend. The higher removal of dyes could be caused by using ultrasonic treatment. The conductivity of dye aqueous solution was decreased with increasing surfactant concentration for the removal of dyes. The CI Reactive Blue 19 from backward extraction was reused for dyeing cotton fabrics, which exhibited the good property.     

Selective control of polyamide dyeing with acid dyes using hydroxypropyl-β-cyclodextrin

The effect of hydroxypropyl-β-cyclodextrin (HPβCD) in the dyeing of polyamide fabric was investigated under conditions that mimic industrial dyebaths where dye mixtures are used. The dyes used were Telon Red BN, Telon Yellow A-2R, and Telon Blue RR. The blue dye complexed with HPβCD whereas the other dyes did not do so under the conditions used. The dyeing results were compared with those obtained using a traditional retarding agent, Albegal B. The exhaustion dyeing data showed that HPβCD mainly affected the dyeing behavior of the blue dye that became encapsulated. In the case of the yellow and red dyes, changes in the overall kinetics of dyeing were observed, resulting in modified exhaustion profiles. In comparison, Albegal B retarded the blue dyeing process and increased the rate of exhaustion of the yellow dye while the exhaustion curve of red dye remained unchanged. The color uniformity of the dyed polyamide was improved when HPβCD was used. This resulted from the more controlled exhaustion rate during the critical phase of the dyeing process.     

Colorimetric studies of benzoquinoline based hot brand monoazo reactive dyes and their dyeing performance on various fibers

A series of hot brand monoazo reactive dyes (9a-l) were obtained by the coupling of diazotized 1Hbenzo[ g]pyrazolo[3,4-b]quinoline-3-ylamine (5) with various cyanurated coupling components (8a-l) in good yield. Synthesized dyes were characterized by various spectroscopic techniques. Their dyeing performances as reactive dyes have been assessed on silk, wool, and cotton fabrics. The percentage dye bath exhaustion and fixation on different fibers were found to be very good. The dyed fabric showed moderate to very good light fastness and good to excellent washing and rubbing fastness properties. Spectral properties and colorimetric data of synthesized dyes have also been studied in detail.     

Compatibility of Natural Dyes on Aluminum Pre-Mordanted Woolen Yarns by Determination of Diffusion Coefficient

In the present research, a method of assessing relative compatibility rating of single and binary mixtures of walnut green shell, cochineal, and weld natural dyes on aluminum pre-mordanted woolen yarns was proposed, where a proportion of the calculated diffusion coefficients of dyes was postulated. To calculate the diffusion coefficient values, the uptake behavior of dyes was derived as the K/S and the exhaustion curves by dyeing the woolen yarn samples with the individual dye as well as with the mixtures of dyes obtained from practical conditions of dyeing. A typical method was employed to dye the samples at two temperatures of 80 and 95 oC. The method proposed for determination of the compatibility of dyes was more verified at higher temperature, that is, 95 oC, against a conventional method of solution analysis. The results of compatibility showed that the selected binary mixtures of cochineal-weld have an excellent compatibility. The other mixtures, that is, walnut green shell-cochineal and walnut green shell-weld showed weak-moderate and very weak compatibility, respectively.     

Dyeing properties of nylon,PET, and N/P mixture fabric with reactive-disperse dyes having a sulfatoethylsulfone group

The dyeing and color fastness properties of two reactive-disperse dyes containing a sulfatoethylsulfone group on nylon, PET and N/P mixture fabrics were examined. The rate of dyeing on nylon fabric was greatly dependent upon dye bath pH. The final dye uptakes at all pH, however, were as high as 97 %. Color strength of the dyed nylon fabric linearly increased up to 0.5 %owf and then slowed down over 1 %owf dyeing. Washing and rubbing fastness of the dyed nylon fabric were excellent, but grade of light fastness was moderate. Dyeability of the reactive-disperse dyes on PET fabric was not much affected by pH, and K/S values of PET fabric dyed at pH 5–8 were lower than those of nylon fabric at all pH examined. Buildup and color fastnesses properties on PET fabric showed the same tendency with nylon fabric. The rate of dyeing of the reactive-disperse dyes on nylon fabric was faster than on PET fabric when both fabrics were dyed simultaneously in the same dye pot, resulting in higher color strength of nylon than PET. The reactive-disperse dyes were found to be adequate to the one-bath, one-step dyeing of N/P mixture fabric when applied at pH 5 and 120 °C.     

Synthesis,characterization, and properties of ethoxylated azo dyes

The nonionic surfactant properties of ethoxylated azo dyes, such as cloud point and surface tension have been investigated. The synthesized ethoxylated azo dyes could dye polyester fabric without any special pre-treatment. When the average number of ethylene oxide (EO) in the ethoxylated azo dye reached 6, its fixation could exceed 90% from the thermosol dyeing process. The average degree of condensation of ethylene glycol in the chain was interrelated with the dyeing results and did not affect on the maximum absorption wavelength (λmax) of the polyoxyethylene dye. When the average length of polyoxyethylene chain decreased, the molecular weight of dyes became smaller and the fixation of dyes was improved.     

Dyeing performance of disperse dyes based on 2-aminothiazole for cellulose triacetate and nylon fibers

A series of monoazo disperse dyes based on 2-amino-4-phenylthiazole was prepared using variousN,N-dialkylaniline derivatives as the coupling component. The dyes were characterized by IR spectral studies, visible absorption spectroscopy and elemental analysis. The dyeing performance of these dyes was assessed on cellulose triacetate and nylon fibers. These dyes were found to give a wide range of colour shades varying from bright red to royal blue with very good depth, brightness and levelness on fibers. The dyed fibers showed good to very good light fastness and very good to excellent fastness to washing, perspiration, rubbing and sublimation. The dyebath exhaustion and fixation on the fibers were found to be very good.     

Dyeing characteristics of Nylon,cotton and N/C mixture fabrics with reactive-disperse dyes containing a sulphatoethylsulphone group

The dyeing and color fastness properties of three reactive-disperse dyes containing a sulphatoethylsulphone group on Nylon, cotton and N/C mixture fabrics were examined. Reduction-clearing was more effective in removing the unfixed dyes than soaping since the reactive-disperse dye became hydrophobic during dyeing process. Nylon was dyed well with three reactive-disperse dyes at pH 5∼8 and difference in chemical structure between dyes did not affect the final color strength of the dyed Nylon fiber, but their build-up properties on Nylon were not so good. The color strength of the dyed cotton was not as high as that of Nylon. The color strength of cotton increased by lowering dyeing temperature when the reactive-disperse dyes having hydroxy group were used. Nylon absorbed more dye molecules than cotton in simultaneous dyeing, the color difference between Nylon and cotton could be reduced as the dyeing temperature decreased. N/C mixture fabric was dyed well at 60 °C with the reactive-disperse dyes having hydroxyl group when applied at pH 7 and 60 °C, and their build-up properties were good. It was also found that washing fastness and rubbing fastness of dyed Nylon, cotton and N/C fabrics with the reactive-disperse dyes were excellent, while light fastness was moderate.     

Study on the dyeing properties of hemicyanine dyes. I. Acrylic fabrics

Three hemicyanine dyes were employed in dyeing acrylic fabrics following traditional cationic dyeing procedures. The influence of the substituting groups of the dye molecule on the sorption rate and sorption isotherms was analyzed. The results showed that those dyed acrylic fabrics using hemicyanine dyes had obvious fluorescent effect in the spectra range 550–750 nm. In addition, according to the EN-471 standard (2003), the chromaticity of dyed acrylic fabric was calculated to evaluate whether hemicyanine dye could meet the requirements of the fluorescent dye for high visibility warning clothing.     

A study of reusing vinyl sulfone based reactive dye for dyeing cotton fiber

Reactive dye is a popular dye for dyeing cotton fiber due to its very good color fastness which is explained by the formation of covalent bond between dye and fiber. In this study, practicality of reuse of reactive dye by compensating for the hydrolyzed part of the dye solution is examined. A monofunctional dye (vinyl sulfone type) was used and it was found that dyeing cotton fiber with reused dyebath is possible. Since bifunctional dye can improve the chance of dye-fiber bond formation, vinyl sulfone based bifunctional reactive dyes were also selected in this study. Three types of bifunctional dyes were used and they basically share the same vinyl sulfone group; other reactive groups are monochlorotriazine, dichlorotriazine and vinyl sulfone. Such dyes were chosen in order to compare their respective efficiencies under the effect of one common reactive group. The aim of this study was to compare the effect of hydrolyzed and unhydrolyzed proportions of mono-and bifunctional reactive dyes on cotton fiber and study the possibility and efficiency of the two different reuse dyebath systems.     

Study on the dyeing of wool fabrics with Phytolacca berry natural dyes

Dyeing of wool fabrics with natural dyes from Phytolacca berries has been studied. The effect of dye concentration, dye bath pH, dyeing time and temperature were discussed. The influence of chitosan application on the dyeing properties of wool fabrics was investigated. The SEM photographs of chitosan treated wool fabrics clearly depict the deposition of chitosan on the fibers. The effect of chitosan concentration, dye bath pH, dyeing time and temperature has been studied by orthogonal experiment. It has been proved that the dyed wool samples pretreated by chitosan have higher color fastness, faster dyeing rate, and better antibacterial properties compared with untreated ones.     

Dyeing of synthetic fabrics in water using azoic dyes based on boronic acid derivatives

Development of water-soluble dyes for the dyeing of different textile fabrics is essential for the textile industry due to ecological and economical reasons. In this study, a series of new azoic dyes were prepared by diazotization reaction between the phenyl boronic acid and different aniline derivatives, and their dyeing capacity in aqueous solution was evaluated. The synthesized boronic azo dyes present good water solubility and can dye polyamide (nylon), wool, silk, and cellulose acetate fabrics. The effect of factors such as concentration of dye, dyeing temperature, and pH on the level of color strength (K/S) was studied. The dyeing results showed that higher color strength K/S (about 16) and fastness properties (about 4/5) with boronic acid dyes were achieved at higher temperatures avoiding the use of surface agents, mordants, and other polluting chemical additives.     

Extraction of natural dye from <Emphasis Type="Italic">Coreopsis tinctoria</Emphasis> flower petals for leather dyeing − An eco-friendly approach

This study evaluated the extraction of two colors of dye (yellow and brown) from Coreopsis tinctoria flower petals using ultrasound and the dyeing of leather with the extracted dyes as a source of nontoxic and eco-friendly dye. The results showed an increase in the dye extraction values with increasing time at 100 W ultrasonic power at 80 °C for 1 h. Leather dyeing was optimized with the aid of ultrasound and magnetic stirring. The optimum leather dyeing conditions, with respect to the dye uptake, dye penetration and intensity of the color, were determined to be 12 % dye concentration, 100 W power, 1,000 rpm, and pH 7.0 for 60 min at 80 °C. It was shown that sonication improves dye exhaustion from a 90 % to 60 % rating for 1 h of dyeing time. The dyed leather was assessed by reflectance measurements and compared with visual assessment data. The fastness properties of dyed leather samples showed good fastness against washing, light, and dry and wet rubbing. The strength properties were not significantly altered and the bulk properties, such as softness, were found to be improved by the use of Coreopsis tinctoria yellow and brown dyes using an ultrasonic and magnetic stirring dyeing process.     

Dispersant-free dyeing of poly(lactic acid) knitted fabric with temporarily solubilized azo disperse dyes

Poly(lactic acid) (PLA) is known for environmentally friendly material as it is derived from annually renewable crops and biodegradable. Dispersant-free dyeing of PLA fabric with three temporarily solubilized azo disperse dyes which contain β-sulfatoethylsulfonyl group was investigated and their dyeing and fastness properties were compared with those of commercial disperse dyes. The temporarily solubilized azo disperse dyes were successfully applied to PLA fabric without the use of dispersant. The color yield on PLA fabric was dependent on dyebath pH and dyeing temperature as well. The optimum results were obtained at pH 7-8 and 110 °C. The dyes showed markedly higher color yield on PLA fabric when compared to commercial disperse dyes. Wash fastness was very poor to poor but light fastness was good. The COD levels of the dyeing effluent from the temporarily solubilized disperse dyes were considerably lower than those from commercial disperse dyes.     

Studies on antimicrobial activity for multidrug resistance strain by using phenyl pyrazolones substituted 3-(4-aminophenyl)-2-phenylquinazolin-4(3H)-one derivatives in vitro condition and their dyeing performance

Heterocyclic monoazo quinazolinone based azo dyes derived by the diazotization of 3-(4-aminophenyl)-2-phenylquinazolin-4(3H)-one with various phenyl pyrazolones based coupling components. All the heterocyclic azo dyes have been characterized by their percentage yield, UV-VIS spectroscopy, elemental analysis, IR spectroscopy, ¹H NMR spectroscopy, and dyeing performance on silk, wool, nylon, and polyester fibers. All the dyes gave moderate to excellent fastness properties on each fiber. The main focus was to synthesize heterocyclic monoazo dyes that give good dyeing property along with pharmacological activity (anti bacterial and antifungal). Therefore, the synthesized compounds were examined for their antimicrobial activity at various concentrations using well-known Kirby-Bauer disk diffusion method.     

Acid dyeing properties of meta-aramid fiber pretreated with PEO45-MeDMA derived from [2-(methacryloyloxy)ethyl] trimethylammonium chloride

A diblock copolymer (PEO₄₅-MeDMA) derived from [2-(methacryloyloxy)ethyl]trimethylammonium chloride (MeDMA) was synthesized and applied to the dyeing of the meta-aramid fibers with some acid dyes. This copolymer created positive charges on meta-aramid fiber surface and a strong attraction with anionic groups of acid dyes. Meta-aramid fabric was pretreated using the synthesized copolymer and then dyed with two commercial acid dyes. The dyeability was found to be directly dependent on the concentration of PEO₄₅-MeDMA, pH in the dyebath as well as dye concentration. The color fastness of the copolymer pretreated dyed fabric was also evaluated.     

Synthesis of cationized anthraquinone dyes and their dyeing properties for meta-aramid fiber

Due to compact structure of meta-aramid fiber caused by the intermolecular hydrogen bondings of amide groups, the degree of crystallinity increased, thus its poor dyeing properties arises. Among commercial dyes used in many previous researches, the basic dyes showed comparatively higher exhaustion yields as comparing to those of disperse dyes and acid dyes. The anthraquinone moiety was adopted for good performances of light fastness on meta-aramid fiber. In this study, eight of anthraquinone dye was synthesized. The three of them were obtained from chloro-anthraquinone, by Ullmann reactions with the corresponding heterocylic residues such as morpholine and one of them was obtained from lueco quinizarine by condensation with the corresponding heterocylic residues. The others were prepared by quaternization from dyes above. The synthesized disperse and cationic dyes were dyed on meta-aramid fibers and investigated for their build-up dyeing properties and wash fastness.     

One-Bath Union Dyeing of Wool/Acrylic Blend Fabric with Cationic Reactive Dyes Based on Azobenzene

Three unreported cationic reactive dyes based on azobenzene were synthesized using a novel synthetic route. Synthesized dyestuffs containing three primary color dyes were characterized by FTIR, H-NMR, LC-MS, Element Analysis and UV-vis spectroscopic techniques. The absorption spectra of dyes were measured in three solvents with different polarities. The dyeing and color fastness properties of three cationic reactive dyes on wool, acrylic and wool/acrylic blend fabrics were determined. The optimum pH for wool and acrylic fabrics were 6 and 5, respectively. Effect of temperature, time on dyeing properties and color fastness properties on wool fabric showed the same tendency with acrylic fabric. The K/S value of wool fabric dyed with three dyes was similar to that of acrylic fabric when both fabrics were dyed simultaneously in the same dyebath using low dye concentration. Wool/acrylic blend fabric dyed with three cationic reactive dyes using onebath one-step method achieved good union dyeing property and excellent color fastness.     

Improving the dyeability of poly(lactic acid) fiber using N-Phenylaminopropyl POSS nanoparticle during melt spinning

The dyeability of poly(lactic acid) (PLA) fiber strongly depends on disperse dye structure due to the low dyeing temperature and the short dyeing time. Thus, the dye uptake value of PLA fiber is low for some disperse dyes and is needed to be improved. In the current study, the dyeability of PLA fiber is improved with the addition of N-Phenylaminopropyl polyhedral oligomeric silsesquioxane (AP-POSS) during melt spinning process. The effects of dyeing conditions including dyeing temperature and time, disperse dye type and AP-POSS concentrations are investigated on the dyeability properties of PLA fiber samples. The tensile, thermal and morphological properties of fiber samples are also characterized by tensile testing, differential scanning calorimeter (DSC), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). As the added amount of AP-POSS increases, the percent crystallinity increases and the tensile strength reduces. According to the dyeing results, AP-POSS is very effective for increasing the dyeability of PLA fiber especially for disperse dyes with low dye uptake values.