pH-Sensitive Dye-Polyether Derivatives as Dispersants for Its Parent Dye. Part 2: Dispersion Stability and Dyeing Performance

The influence on adsorption of dye-polyether derivatives of different molecular weights and degrees of hydrophilicity/hydrophobicity on the dispersion behavior of C.I. disperse red 60 has been investigated. A range of experimental methods including derivative adsorption isotherms, particle size measurements and dispersion stability tests were used to assess the dispersing capability of the derivatives. The adsorption mainly depends on the hydrophobicity of the derivative but its molecular weight, while the dispersion stability is related to both the adsorption layer and the hydration layer. The results showed that good dispersion stability were obtained even when the weight ratio of dye/dye-polyether derivative was quite low. The dyeing performance of the prepared dispersions was also evaluated by comparing with that of commercial dye. The chemical oxygen demand of the dyeing effluent could be reduced dramatically by the adoption of the dye-polyether derivatives, while the dye exhaustion was higher and the quality of the dyed polyester fabric was at least as good as the dyeing with the commercial dye.     

Synthesis of Some New Thiazolo[3,2‐a]pyrimidine Derivatives and Their Applications as Disperse Dyes

A series of novel thiazolo[3,2‐a]pyrimidine derivatives were synthesized by using β‐ketoanilides 1a–c as starting materials and as key intermediates for preparation of new pyrimidinecompounds 3a–e and fused heterocyclic pyrimidine derivatives 5a–c . The new compounds were transformed to disperse dyes 6a,b and 7 . The chemical structures were elucidated by spectroscopic and elemental analyses and found to be in good agreement with the proposed structures. The versatility of compounds 6a,b and 7 for textile dyeing as disperse dyes was reported. The synthesized dyes were applied to polyester fabrics by using high temperature dyeing method at 120°C. The dye uptake expressed as color strength (k/s) of the dyed samples has been measured. Moreover, the color strength was examined in detail. In addition, the position of color in CIELAB coordinates (L*, a*, b*, h, and C*) was assessed. The color fastness of the dyed samples gave excellent results for washing and rubbing; however, the light fastness was moderate. Raman spectra of dyed samples unequivocally excluded ring dyeing and found to match with the proposed structures.     

Design and synthesis of novel antimicrobial acyclic and heterocyclic dyes and their precursors for dyeing and/or textile finishing based on 2-N-acylamino-4,5,6,7-tetrahydro-benzo[b]thiophene systems

A series of novel polyfunctionalized acyclic and heterocyclic dye precursors and their respective azo (hydrazone) counterpart dyes and dye precursors based on conjugate enaminones and/or enaminonitrile moieties were synthesized. The dyes and their precursors are based on 2-cyano-N-(3-cyano-4,5,6,7-tetrahydrobenzo[b]thiophen-2-yl)-acetamide, 2-ethoxycarbonyl-N-(3-cyano-4,5,6,7-tetrahydrobenzo[b]thiophen-2-yl)-acetamide or 2-phenylcarbamoyl-N-(3-cyano-4,5,6,7-tetrahydrobenzo[b]thiophen-2-yl)-acetamide systems as precursors. The latter compounds were used to synthesize polyfunctional thiophene-, thiazole-, pyrazole, pyridine-, pyrimidine-, oxazine-, as well as acyclic moieties. The dyes and dye precursors were characterized by elemental analysis and spectral methods. All dyes and their precursors were screened in vitro and evaluated for both their antibacterial and antifungal activities. MIC data of the novel dye systems and their respective precursors showed significant antimicrobial activity against most tested organisms. Some compounds exhibited comparable or even higher efficiency than selected standards. Dyes were applied at 5% depth for disperse dyeing of nylon, acetate and polyester fabrics. Their spectral characteristics and fastness properties were measured and evaluated.     

Silicone nanomicelle dyeing method on polyester fibre: Comparative evaluation of chemical properties,fastness properties,and DFT

Disperse Red 177(9a), Disperse Red 343(9b), Disperse Blue 165(9c), Disperse Blue 165.1(9d), Disperse Blue 366(9e), and Disperse Blue 148(9f) were examined in the solvent. During silicon nanomicelle dyeing, we employed 9(a–f) azo disperse dyes on polyester. On polyester fabric, dye 9(a–f) offers equal washing, light, and rubbing fastness in both the conventional and silicone nanomicelle techniques. The dye can now be transported directly into the fibre core without the use of auxiliary dyes owing to the reduction in the particle size of azo dyes, which is made possible by nanoemulsions superior dispersion. The levelling property of the dispersed dye is enhanced by the dyeing process. When both techniques are applied, the lightfastness properties of all dyes are improved. It provides a very good to outstanding protection factor for textile materials. These 9(a–f) azo disperse dyes have moderate to outstanding photostability, net electrophilicity index, and lightfastness.     

Synthesis and Characterization of Novel Monoazo Naphthalimide Disperse Dyes Containing Carboxylic Acid Group with High Heat Fastness Properties

A group of novel monoazo disperse dyes containing carboxylic acid‐1,8‐naphthalimide group has been synthesized. All intermediates and dyes were purified by recrystalization and the column chromatography method. The purified products were characterized by ¹H NMR, ¹³C NMR, FTIR, DSC, UV‐VIS and Elemental Analysis. Spectrophotometric investigations of the synthesized dyes in different solvents were carried out in order to obtain their absorption maxima, molar extinction coefficients and solvatochromic effects. The absorption maxima of the synthesized dyes in acetone varied (513‐549 nm) and the molar extinction coefficient was (17405‐38939 l/mol cm). By changing the media from chloroform to DMF, the solvatochromism effect for all dyes increased. Dispersion of the synthesized dyes was prepared in water containing dispersing agent and applied to polyester fabrics. The dyed fabrics showed that all of the synthesized dyes were suitable for coloring polyester fibers, producing deep red to bluish red with very good fastness properties.     

Preparation and application of a β-cyclodextrin-disperse/reactive dye complex

A disperse and a disperse/reactive azo-dyes were prepared and characterised with spectroscopic methods. The complexes with β-cyclodextrin were prepared by a dry milling method. The characterisation of the complexes in solid state was performed by ¹³C CP MAS NMR, FT-IR, Raman spectroscopies and TGA–DTA analysis. The presence of the complexes in solution was evidenced with ESI-MS experiments. The products were used to dye synthetic (nylon, PET), natural (cotton) and cotton-PET blend fibres. Colour intensity and uniformity were evaluated by means of tristimulous colorimetry. β-Cyclodextrin, used as additive in dyeing baths, enhanced the colour intensity and uniformity of dyed samples. The complexes gave rise to a generalised good result. The disperse/reactive dye showed better fastness to washing properties on nylon 6 and cotton fibres. β-Cyclodextrin easily substituted the surface active agents, normally used in industrially dyeing processes, without loss in dyeing quality as dyeing uniformity, intensity and washing fastness.     

Disperse Dyes Based on 5‐Arylazo‐thiazol‐2‐ylcarbamoyl‐thiophenes: Synthesis,Antimicrobial Activity and Their Application on Polyester

A series of novel 5‐arylazo‐thiazol‐2‐ylcarbamoyl‐thiophene derivatives was synthesized, and their chemical structures were secured by elemental and spectroscopic analyses. Their versatility for pharmaceutical purposes and textile dyeing as disperse dyes were reported. The synthesized dyes were applied to polyester fabrics by using high temperature dyeing method at 130°C. The dyed polyester fabrics displayed very good washing and perspiration fastness and moderate light fastness. Finally, the synthesized compounds showed biological activities against Bacillus subtilis, Staphylococcus aureus (Gram positive bacteria), Escherichia coli, and Pseudomonas aeruginosa (Gram‐negative bacteria), while no effect had been reported against fungi. The minimum inhibitory concentration of the most active compound was evaluated.     

Disperse dyes derived from 2-amino-5-mercapto-1,3,4-thiadiazole

Some novel heterocyclic monoazo dyes based on 2-amino-5-mercapto-1,3,4-thiadizole have been synthesized by coupling with various N-phenylacrylamide derivatives. The dyeing performance of these dyes was assessed on polyester fabrics. IR and visible spectra of the dyes were examined. The percentage dye bath exhaustion, fixation, and various fastness properties of the dyes were also determined. These dyes were found to give brownish-orange to reddish-pink shades on dyeing with good depth, levelness, and brightness on fabric. The dyed fabric showed a good to excellent fastness to washing, rubbing, perspiration, and sublimation.     

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

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

分散染料染色法制备的彩色聚(苯乙烯-丙烯酸)纳米球

在低于聚合物纳米球玻璃化转变温度(110.69 ℃)的条件下,用两种分散染料对聚(苯乙烯-丙烯酸)[P(St-co-AA)]纳米球染色,研究了染色温度(75~95 ℃)和染料用量(1%~5%)对纳米球上染料吸附量的影响。 结果表明,染色温度越高,分散染料用量越大,所得到聚合物纳米球的颜色越深越鲜艳。 分子结构中氨基和羟基数量多的分散蓝2BLN在纳米球上的吸附量低于相同染料用量时分散红FB的吸附量。 经过染色后纳米球的表面变得很粗糙,粒径增加23 nm。 用彩色纳米球对经过阳离子化处理的棉织物进行染色,利用很少量的彩色纳米球,就可以使织物获得较深且鲜艳的颜色。     

Chemical recycling of PET waste into hydrophobic textile dyestuffs

The paper aims at effective chemical recycling of poly(ethylene terephthalate) (PET) fiber waste into useful products, such as hydrophobic disperse dyes for synthetic textiles. For this, PET fiber waste was glycolytically depolymerized using excess of ethylene glycol in the presence of sodium sulfate as catalyst. The product, pure bis(2-hydroxyethylene terephthalate) (BHET) was obtained with >60% yield by successive recrystallization. In order to synthesize hydrophobic disperse dyes, applicable to synthetic textile fibers, BHET was converted to bis(2-chloroethylene terephthalate), reacted with the p-nitro benzoic acid, reduced and then reacted with bromine and potassium thiocyanate to get benzothiazole derivative. Coupling with N,N-diethylaniline produced a bright yellow disperse dye (Dye A). Similarly, coupling of p-amino benzoic ester with N,N-diethylaniline led to an orange colored disperse dye (Dye B). These dyes were applied onto polyester fabric by conventional method. Results in terms of depth of dyeing, evenness and the performance characteristics were found to be promising.     

High efficiency ultra-deep dyeing of cotton via mercerization and cationization

A potentially environmentally responsible dyeing procedure for ultra-deep shades on cotton was developed using a cationization method in combination with mercerization. The effects of both treatments on dyeing performance and colorfastness properties of cotton fabrics dyed with reactive dyes were analyzed individually and in combination. Both mercerization and cationization have been proved to be effective in increasing the depth of shade on cotton. The colorfastness properties, except colorfastness to wet crocking, of mercerized–cationized cotton fabrics dyed without salt were much better than untreated cotton dyed using a conventional dyeing procedure. Unlike untreated cotton fabrics, the concentration of Na₂CO₃ in the dyeing process of mercerized–cationized cotton fabrics was lowered from 20 to 5 g/L without compromising dye fixation and colorfastness properties. With low concentrations of dyes and Na₂CO₃ and no electrolyte in the dye bath effluent, the dyeing procedure of mercerized–cationized cotton fabrics for ultra-deep shades is potentially a more environmentally benign method than conventional dyeing with reactive dyes.     

Improvement in the Leaching Behavior of Dye-Doped Modified Silica Layers Coated onto Paper or Textiles

Leaching stability is important when refining paper or textile surfaces with sol-gel silica layers that contain incorporated dyes or other components. First studies show a simultaneous increase in dye and Si concentration in the wash-out solution, indicating that the gradual dissolution of the complete composite layer plays an important role in the leaching process. The leaching stability of silica layers containing incorporated model dyes Aniline Yellow and Acid Orange 10 on different flexible substrates (cellulose paper, polyamide and polyester fabrics) could be improved in a number of different ways: (i) pretreating the substrate with coupling agents such as epoxyalkyl-silanes, (ii) fixing the dye within the silica layer by mixing it with alumina or alkylammonium compounds, and (iii) chemically fixing the dye by bonding it covalently to the silica matrix.     

Anthraquinone and Azo Dyes in Dyeing Processes of PET Films and PET Knitted Fabrics Using Supercritical CO2 Medium

Summary: Dyeing processes using supercritical fluid present advantages over the conventional dyeing process using aqueous medium. Previous works from our group on polymeric fibers such as N,N-dimethylacrylamide (DMAAm) modified poly(ethylene terephthalate), PET, showed higher sorption of disperse dyes in supercritical medium. Furthermore, recent studies showed that the association of UV radiation and DMAAm treatment leads to a better incorporation of dyes in modified PET soaked in aqueous medium. In this work, modified and non-modified PET knitted fabrics (KF) were dyed in supercritical CO₂ medium. Azo and anthraquinone dyes were used in order to compare the extent of incorporated dye in PET films and PET KF in supercritical CO₂. The dyeing process variables were studied by factorial design and by a response surface methodology (RSM) technique. The anthraquinone dye presented a better incorporation in PET than the azo dye. The UV light exposure and the dyeing times inputs showed positive main effects in the incorporation of dyes in PET films and PET KF. From the RSM data, DMAAm and UV light modified PET KF presented 7.43 mg of incorporated azo dye by g of PET if the optimized dyeing conditions, time: 135 min and pressure: 212 bar would be used. In the respective optimized dyeing conditions for the anthraquinone dye, time 150 min and pressure 229 bar, the incorporated dye would be 22.9 mg of dye by g of PET.     

Naphthalimide based disperse dyes for nylon 6 and polyester (pet) fibers: Synthesis and evaluation of technical properties in the presence of urea

Technical properties of two naphthalimide based disperse dyes on nylon 6 and polyester fibers were investigated in the presence of urea.The two naphthalimide based disperse dyes were synthesized.The dyes were purified and then fully characterized using ~1H-NMR,FTIR and melting point analysis.Dispersion of the dyes was prepared in water and applied on nylon 6 and PET fibers.The dyes offered good build-up properties on the substrates.In order to increase dye adsorption of the substrates,urea was added into...     

CI Reactive Black 5 dye as a visible crosslinker to improve physical properties of lyocell fabrics

Bi-functional reactive dyes have been used for reducing the fibrillation of lyocell fibres. The sole influence of CI Reactive Black 5 dye on the fibrillation tendency of lyocell single jersey knitted fabrics was investigated by dyeing with different concentrations (35 g/L for medium shade and 70 g/L for dark shade), dyeing without dyestuff and by decolouration process after each dyeing. The fibrillation tendency of lyocell fibres was accessed by means of fibre wet abrasion resistance and fibrillation number. Nitrogen content was used as indication of the amount of reactive dye in fabrics during dyeing and decolouration processes. The correlation between fibre fibrillation tendency and colour values of fabrics was found. Due to the fibrillation reduction, pilling formation in dyed lyocell fabrics was improved. As colour values can estimate the dye fixation and reduction in fabrics, reactive dye can be used as a visible marker for crosslinking effect on lyocell fabrics.     

杂环-双氰乙基系列分散染料的合成、表征及染色性能

以4个杂环芳香胺为重氮组分, 3个N,N-二氰乙基芳香胺为偶合组分, 经重氮化、 偶合反应合成了12个杂环-双氰乙基系列偶氮物; 采用紫外-可见吸收光谱、 红外光谱及核磁共振氢谱等对其结构进行了表征; 还考察了它们在涤纶织物、 乙酰化杉改性木粉和氰乙基化改性木粉上的染色性能. 结果表明, 12个偶氮物为目标产物, 在N,N-二甲基甲酰胺(DMF)中的最大可见吸收波长为417～621 nm, 摩尔吸光系数均大于10⁴. 这些化合物染色涤纶织物的色光分属黄色、 红色、 紫红色和蓝色系列, 并具有高水洗牢度和高日晒牢度; 染色乙酰化木粉和氰乙基木粉的色光和水洗牢度与染色涤纶织物相近. 这12个分散染料具有色谱范围广、 色泽鲜艳、 高发色强度和高牢度等特点, 可用于多种纤维的染色.     

Dyes with high affinity for polylactide

Attempts were made to develop dyes with high affinity for polylactide as an alternative to the existent commercial disperse dyes. The dyes synthesized according to the affinity concept of dye to polylactide exhibited excellent dyeing properties on polylactide compared with the commercial disperse dyes.     

Synthesis and dyeing properties of new disazo disperse dyes for polyester and nylon fabrics

Diazotized aryl amines were coupled with two stenhouse salt namely, N-(5-phenylamino-penta-4-ol-2,4-diene-1-ylidene)anilines hydrochloride [S₁ (RH) or S₂ (ROH)] to furnish two series of disazo disperse dyes (S₁D_1–10 and S₂D_1–10). The structure of all the dyes was established by estimating number of azo groups, elemental analysis and spectral studies (IR, ¹H-NMR, UV/Visible). The structure–property relationship was discussed by using electronic absorption spectra of the dyes. These dyes were applied to polyester and nylon fabrics as disperse dyes by using temperature exhaust dyeing method. The relevant dyeing characteristics, such as dyeability on fabrics, wash-fastness and light-fastness were evaluated. Fabrics dyed with these dyes furnished generally deep and bright intense hues ranging from light yellow to orange to reddish brown. The color fastness of the dyed fabric was assessed by determining wash-fastness and light-fastness properties.     

Development of the Microemulsion Electrokinetic Capillary Chromatography Method for the Analysis of Disperse Dyes Extracted from Polyester Fibers

The study aimed to develop a method for the separation of dispersed dyes extracted from polyester fibers. Nine commercially available disperse dyes, which were used to dye three polyester fabrics, were tested. Extraction of dyes from 1 cm long threads was carried out in chlorobenzene at 100 °C for 6 h. The separation was performed using microemulsion electrokinetic capillary chromatography (MEEKC) with photodiode array detection. Microemulsion based on a borate buffer with an organic phase of n-octane and butanol and a mixture of surfactants, sodium dodecyl sulphate and sodium cholate, were used. The addition of isopropanol and cyclodextrins to microemulsion resulted in a notable improvement in resolution and selectivity. The content of additives was optimized by using the Doehlert experimental design. Values of the coefficient of variance obtained in the validation process, illustrating the repeatability and intermediate precision of the migration times fit in the range of 0.11–1.24% and 0.58–3.21%, respectively. The developed method was also successfully applied to the differentiation of 28 real samples—polyester threads collected from clothing. The obtained results confirmed that proposed method may be used in the discriminant analysis of polyesters dying by disperse dyes and is promisingly employable in forensic practice.