Kinetics of dyeing of polyester with CI Disperse Blue 79 in supercritical carbon dioxide

Polyester fabric was dyed with CI Disperse Blue 79 in supercritical carbon dioxide and the effect of temperature and dyeing time on dye uptake was studied. On raising the temperature at constant pressure the dye uptake gradually increased, reaching equilibrium after 60 min. The diffusion coefficient at different temperatures and the activation energy of the dye on polyester fabric in supercritical carbon dioxide have been determined. The latter was found to be considerably lower than the corresponding figure for conventional dyeing.     

Compatibility of a disperse dye mixture in supercritical carbon dioxide dyeing

The compatibility of three disperse dyes, CI Disperse Orange 30, CI Disperse Red 167 and CI Disperse Blue 79, which are commonly used as a trichromatic combination for conventional dyeing, was studied in supercritical carbon dioxide dyeing. Both the dyeing rate and the build‐up of the selected dyes were measured. Experimental results showed that they were quite compatible. The dyeings of a binary combination (CI Disperse Orange 30 and CI Disperse Blue 79, mass ratio 1:1) and a ternary combination (CI Disperse Orange 30, CI Disperse Red 167 and CI Disperse Blue 79, mass ratio 1:1:1) at different dye concentrations showed an on‐tone uptake and presented the same metric hue angles. This proved that the selected dyes could form a useful trichromatic combination in supercritical carbon dioxide dyeing. Furthermore, the uptake and exhaustion of the single dyes in supercritical carbon dioxide dyeing were similar to those in aqueous dyeing, implying that the dyeing media play only a minor role in the dyeing of polyester fibres with disperse dyes.     

人造麂皮在超临界二氧化碳中的染色研究

通过改变超临界系统的条件,研究C.I.分散蓝79以超临界CO2为介质对人造麂皮的上粢性能.结果表明,温度和压力都时上染性能有明显影响;C.I.分散蓝79在110℃,22 MPa,染色人造麂皮45分钟,能达到理想效果.染色牢度优于常规水浴染色效果.     

The dyeing of nylon with a microencapsulated disperse dye

Melamine resin microcapsules containing CI Disperse Blue 56 were prepared by in situ polymerisation. The microcapsules were characterised by their thermal properties and morphology, such as particle size and particle size distribution. The dyeing behaviour of the microcapsules on nylon 6.6 was evaluated. The microencapsulated dye exhibited good build-up, levelness and fastness properties. It has been demonstrated that microencapsulated disperse dye can be used to replace commercial disperse dyes in dyeing polyamide fabric without dyeing additives, and the resulting effluent can be easily recycled after filtration.     

Supercritical fluid dyeing of cotton modified with 2,4,6-trichloro-1,3,5-triazine

Supercritical carbon dioxide dyeing of cotton modified with the fibre reactive group 2,4,6-trichloro-1,3,5-triazine has been examined and the results are discussed. The modification of cotton was carried out in acetone, as well as by a new method using water as the solvent. For level dyeing results a degree of fixation of the fibre reactive group on cotton of 3% owf was required without changing the hydrophilicity of the fibre. The results show that dyeing of modified cotton is possible with dyes containing hydroxy or amino groups which react via a substitution reaction with the chlorine atoms of 4,6-dichloro-1,3,5-triazine-2-yl on the fibre surface. The K/S values at 383 nm of modified cotton dyed with CI Disperse Yellow 23 were found to be between 1.44 and 4.79 depending on the dyeing conditions used. The washing, rubbing and light fastness data that were obtained were between 3 and 5.     

Dyeing nylon-6,6 with some hydrophobic reactive dyes by supercritical processing

Nylon-6,6 fibers, spun from the polyamide (polyhexamethylene diamine adipate), are increasingly required to be dyed with high washing fastness. Nylon-6,6 were dyed with hydrophobic reactive dyes synthesized in our laboratory, using supercritical carbon dioxide as the solvent system. Structures of four hydrophobic reactive dyes and their covalent force with nylon-6,6 fibers were confirmed by FTIR, MS and NMR analysis. Nylon-6,6 were also dyed with C.I. disperse red 2 to compare the result with specimen dyed by hydrophobic reactive yellowish red dye (dye I), which further demonstrated that covalent force was formed between dye-fiber interaction. Dye uptake was moderate to good and the dyed fabrics had very good fastness properties. Results of the latter studies indicated that dyeing nylon-6,6 in supercritical carbon dioxide is feasible.     

Studies toward a universal dye for textile fibres

A new organic dye was synthesised as part of an approach to producing a dye that could be applied to any of a variety of widely used fibre types. The dye synthesised is best described as a disperse-reactive dye and was obtained from a sequence of reactions that used an acid yellow dye as a starting compound. Dichlorotriazine was used as the reactive group in the target dye and the chemical structures of the new dye and its precursors were confirmed using ¹H NMR, mass spectrometry and FTIR analyses. In the neutral form, the dye was suitable for polyester, nylon and wool fibres. When the pH was adjusted to 9 it dyed cotton, albeit in a pastel shade only. By adding N, N -dimethylethylenediamine to the dyebath, the dye could be applied to acrylic fabric at pH 5. The fastness of the dyed fibres was also evaluated.     

Microwave‐assisted dyeing of poly(butylene terephthalate) fabrics with disperse dyes

In this study, conventional heating and microwave dielectric heating in the exhaust dyeing of poly(butylene terephtalate) fabrics with disperse dyes were studied in order to determine whether microwave heating could be used to increase the dyeability of poly(butylene terephtalate) fibre in shorter processing times and enable dyeings of adequate wet fastness to be obtained. Accordingly, the samples of 100% poly(butylene terephtalate) single jersey knitted fabric were dyed with CI Disperse Yellow 160 and CI Disperse Yellow 42, CI Disperse Red 177 and CI Disperse Red 91, CI Disperse Blue 79:1 and CI Disperse Blue 54 at 98 °C with or without microwave dielectric heating. The colouristic properties, colour fastnesses and the tensile properties of the dyed fabrics were investigated and compared with each other. Microwave dielectric heating is regarded as a tool for ‘green chemistry’ and provides many advantages over conventional heating without any deterioration in the properties of the dyed materials. Microwave heat dyeing enhances the exhaustion and the fixation of dye, and good colour fastnesses and repeatability in dyeings are achieved in short heating times of the dyebath.     

Dyeing poly(lactic acid) fibres in supercritical carbon dioxide

A study has been conducted into the dyeing of poly(lactic acid) fibres in supercritical carbon dioxide. The fibres were completely dyed using disperse dyes at 50 °C as shown by fibre cross-sections, although high colour depths in dark shades still prove challenging. Dye uptake increased significantly at temperatures ≥80 °C. At 95 °C in supercritical carbon dioxide, shrinkage and hardening of raw poly(lactic acid) were observed which could partly be overcome by the supercritical carbon dioxide extraction step. Afterclearing with cold supercritical carbon dioxide (to remove unfixed dye after dyeing) decreased the colour depth and led to non-uniform dyeing results on poly(lactic acid). Wash and rub fastness was good to very good also when poly(lactic acid) was not aftercleared in supercritical carbon dioxide. Fibre damage and elongation at break in supercritical carbon dioxide were similar to water.     

Use of γ-cyclodextrin/epichlorohydrin polymer in merging fabric formation and coloration processes

A candidate polymeric size was synthesised by the polymerisation of γ -cyclodextrin with epichlorohydrin under alkaline conditions. The motivation for the synthesis was to produce a polymer that could not only function as a warp size for fabric formation, but also serve as a host for dye molecules that could subsequently be released after the weaving process, ultimately promoting the merging of fabric formation and coloration processes. The γ -cyclodextrin/epichlorohydrin polymer has been found to promote the dissolution of textile dyes, such as CI Disperse Blue 3, CI Disperse Yellow 82 and CI Disperse Red 91 to yield pad baths capable of evenly coating polyester fabric. Upon padding and subsequent drying, the dye– γ -cyclodextrin/epichlorohydrin polymer pad baths have been used for dyeing the fabric upon thermofixation. Furthermore, cross-sections of fibre dyed in the same manner indicate dye penetration into the fibre.     

Correlation of solubility data of azo disperse dyes with the dye uptake of poly(ethylene terephthalate) fibres in supercritical carbon dioxide

Solubility data of disperse azo dyes in supercritical carbon dioxide are presented for dyeings of poly(ethylene terephthalate) fibres with CI Disperse Red 167:1, carried out at 200–300 bar and 80–120 °C, with varying amounts of adulterants. The same dyeings were also carried out in water for comparison. Scanning electron micrographs were taken of the dyes which show a growth of dye crystals during treatment in supercritical carbon dioxide. The paper reports that at 120 °C, melting of the pure dye CI Disperse Red 167:1 is observed. The presence of adulterants in the dye formulations help prevent agglomeration by acting as spacers between the dye molecules. Dyeings of PETP carried out under conditions of the highest solubility of the dye in supercritical carbon dioxide do not necessarily result in a very high dye uptake. This was shown by pressure- and temperature-dependent dyeing experiments of PETP in supercritical carbon dioxide.     

吡唑啉酮型通用染料的合成与应用研究

以1=(2，5-二氯-4-磺酸基苯基)-5-甲基-5-吡唑啉酮为起始原料、经过一系列反应合成了一支吡唑啉酮型黄色通用染料。希望不需在染浴之外进行其它的化学反应就能用它对不同类型的织物进行染色。这是一个五步合成反应、包括重氮化偶合反应，氯置换反应，缩合反应，水解反应，缩合反应。实验中对第二步和第四步的反应工艺进行了改进，改进工艺后使两步反应的操作简化，成本降低，收率提高合成的染料以三聚氯氰为活性基，该染料及中间体的化学结构，通过^1H核磁共振谱、质谱和红外光谱分析得以表征，在中性染浴中，合成的染料可用于羊毛，丝绸，尼龙，涤纶纤维染色：通过加入N，N-二甲基乙二胺调节pH值为5，可对腈纶纤维进行染色。染料在纤维上的日晒和水洗牢度测试结果表明，染料在晴纶上的日晒、水洗牢度较低：在羊毛、丝绸上有中等的牢度性能；在涤纶、尼龙上日晒牢度较低．水洗牢度较高。     

Afterclearing of disperse dyed polyester with gaseous ozone

The efficiency of ozone treatment for the clearing of disperse dyed polyethylene terephthalate fibres has been examined. The ozone treatment for the clearing of the dyed samples was performed by blowing the ozone gas from the ozone generator on to the wet fabric samples. The results indicated that 3‐ and 5‐min ozonation times were appropriate to achieve comparable wash fastness results with conventional reduction clearing without significant colour differences (ΔE* value) for the samples dyed with CI Disperse Yellow 23 and CI Disperse Blue 79, respectively; however, the ozonation time had to be increased to 15 min for CI Disperse Red 82. Tensile strength tests and scanning electron microscopy analysis indicated that the ozone treatment did not cause any severe damage to the fabrics. Ozone treatment for the afterclearing of disperse dyed polyester fabric can lead to energy and time savings and environmental load reduction when compared with conventional reduction clearing. This study tested a new method of ozone application for clearing of disperse dyed polyester by blowing ozone directly on to the fabric samples. This new method of application has the advantage of being readily adoptable for continuous treatment lines and lower water consumption.     

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

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

Application of sodium benzoyl thiosulphate from aqueous solution to wool and its effect on substantivity of disperse dyes. Part 2: modification of wool with sodium benzoyl thiosulphate

Sodium benzoyl thiosulphate was applied to wool fabric from aqueous solutions in order to covalently bind benzoyl groups to the fibre and thus impart disperse dye substantivity to the modified wool. The modified wool fabric was dyed with a selected model disperse dye, CI Disperse Blue 56, and the wash fastness properties of the dyeings assessed.     

Analysis on the dyeing of polypropylene fibers in supercritical carbon dioxide

Polypropylene fibers were dyed in supercritical carbon dioxide system and the results were compared with those of fiber dyed in water system. Dye uptake value calculated by a UV spectrum indicated that polypropylene fiber dyeing was much better in carbon dioxide than in water. Optical microscopical analysis showed that dye molecules had diffused thoroughly into fiber in CO₂ because of the excellent compatibility between the dye and the CO₂. X-ray and birefrigence analysis demonstrated that plastification caused by the implementation of CO₂ made molecular chain more mobile and led to an increase in the dyeing of polypropylene fibers. Moreover a mechanical test and DSC analysis indicated that the fiber structure was not damaged when the fabric was dyed at 100 °C. Hence dyeing polypropylene using CO₂ as a transport medium was very feasible and worthy of further development.     

Dyeing natural fibres in supercritical carbon dioxide using a nonionic surfactant reverse micellar system

A reverse micellar system in supercritical carbon dioxide has been developed as a dyeing medium. Water-soluble dyes such as reactive dyes and acid dyes could be sufficiently solubilised in the interior of a specially constituted reverse micelle. Protein fabrics, silk and wool, were satisfactorily dyed even in deep shades with conventional acid dyes without any special pretreatment. Cotton cellulose fabric was also dyed with conventional reactive dyes when the electrostatic force of repulsion between dye and cotton was eliminated. Compared to previously proposed supercritical dyeing methods, dyeing of fabrics with this system could be performed at low temperatures and pressures in a short time.     

Rope dyeing of fabric in supercritical carbon dioxide for commerical purposes

A novel method for fabric rope dyeing in supercritical carbon dioxide fluid has been successfully developed for the first time for commercial purposes by employing a custom‐built machine. The influence of parameters such as system pressure, temperature, and dyeing time on fabric colour strength was investigated, and the parameters optimised. Moreover, the level dyeing property, reproducibility, and colour fastness were investigated and evaluated under various conditions. The carbon dioxide recycling efficiency and the running costs of the proposed process in comparison with conventional processes for commercial production purposes were also investigated. The rope dyeing results show significant influence of the process parameters on fabric colour strength. Satisfactory and commercially acceptable products with a good level dyeing property, high reproducibility of coloration, and good fastness, rated at 4–5 or 5 for washing and rubbing, were obtained with supercritical carbon dioxide fluid. Moreover, a carbon dioxide recycling efficiency ranging from 92 to 95.2% was possible. In comparison with conventional dyeing processes, running costs were lowered by employing the proposed process and rope dyeing machine.     

Effects of pressure and temperature on dyeing acrylic fibres with basic dyes in supercritical carbon dioxide

The dyeing of acrylic fibre with CI Basic Blue 47 has been investigated using an ammonium carboxylate perfluoropolyether as an auxiliary in order to perform the reverse micellar system in supercritical carbon dioxide media. The basic dye was satisfactorily solubilised in the interior of the reverse micelle in the system, and dyeability in the supercritical carbon dioxide media was excellent, even in the absence of a retardant and/or an acid. The optimum proton-rich condition for dyeing of acrylic fabric is performed in reverse micelle aggregates and the proton-rich water pool is suitable for dye uptake by the fibre even without the presence of additives. Changes in glass transition temperature of acrylic fibre in the carbon dioxide media also influence the dyeing behaviour of acrylic fabric.     

芳纶1313的超高温高压染色研究

本文采用超高温高压法对芳纶1313进行染色,分别研究了染料种类和染色温度对芳纶1313纱线染色日晒牢度、K/S值及染透性等方面影响,结果发现,分散染料所染纱线的各项染色性能都比阳离子染料和还原染料好;随染色温度升高,日晒牢度、纤维表面颜色深度及其纤维染透性都得到了不同程度的改善,而纱线的断裂强度随染色温度的升高变化不大。