Synthesis and properties of novel aziridinyl azo dyes from 2-aminothiophenes—Part 2: Application of some disperse dyes to polyester fibres

A series of yellow to greenish-blue aziridinyl azo dyes and their azo precursors containing a thienyl coupling moiety has been applied to conventional polyester fibre as well as microdenier polyester by high temperature exhaust dyeing. Heat transferability of these dyes onto polyester fibre has also been examined, using conventional heat-transfer printing techniques. The relevant dyeing characteristics, heat transferability, build-up, dyeability on microfibre polyester, washfastness and lightfastness are given. These aziridinyl dyes are reactive to polyester fibres under HT dyeing conditions. Fabrics dyed with aziridinyl dyes are more resistant to solvent extraction than those dyed with conventional dyes. Residual liquors showed only a pale colour when fabric dyed with aziridinyl dyes was dissolved and then precipitated, whereas a coloured polyester precipitate was obtained.     

Kinetics of thermo-fixation of solvent dyes and pigments in polyester fibres

The diffusion coefficient of a dye in fibres is critical to understanding the dyeing process and coloration quality of products. In this paper, the diffusion kinetics of solvent dyes in the thermosol dyeing of polyester fibres was studied by measuring K / S of the dyed polyester fabrics based on the Kubelka–Munk equation. The diffusion coefficients of two model solvent dyes were estimated with Hill's equation using the experimentally measured K / S values and were found to be in good agreement with those calculated from the traditional extraction method. Such a measurement method was applied to several other solvent dyes and pigments that have different molecular sizes and a good correlation between the measured diffusion coefficients and sizes of these dyes and pigments was found. The results indicate that it is feasible to use K / S measurement of dyed fabrics and Hill's equation to evaluate the kinetics of the thermosol dyeing process under certain conditions.     

溶解度参数在分散染料拼混染色及其他行业的应用（二）

溶解度参数δ是热力学上衡量非极性溶质与溶剂之间作用力的一种方法,自1911年提出这一概念后,历经20世纪30年代以内聚能参数衡量其大小,通过物质汽化热来计算溶解度参数,但是难以汽化的物质,难以测定其汽化热.20世纪60年代多人通过大量实验计算出物质分子结构中的基团的吸引力常数与摩尔体积两者总和之商求得溶解度参数,简化了溶解度参数的计算.20世纪80年代未,将此概念用到分散染料对PET聚酯纤维染色中,通过计算,PET的δ值为10.79,而传统PET的分散染料δ都在10.30 ～ 11.6之间,两者相容性很好,因此染色性能与牢度性能俱佳.将该方法引用到分散染料拼混和染厂拼色,可获得极佳效果.PTT聚酯的δ值为10.50,传统分散染料也适用它的染色.PLA纤维实际上是一类脂肪族聚酯纤维,性能与PET、PTT不同,它的δ值为12.8.显然使用传统分散染料达不到很好效果,亟待研究开发PLA专用分散染料.     

溶解度参数在分散染料拼混染色及其他行业的应用（一）

溶解度参数δ是热力学上街量非极性溶质与溶剂之间作用力的一种方法,自1911年提出这一概念后,历经20世纪30年代以内聚能参数衡量其大小,通过物质汽化热来计算溶解度参数,但是难以汽化的物质,难以测定其汽化热,20世纪60年代多人通过大量实验计算出物质分子结构中的基团的吸引力常数与摩尔体积两者总和之商求得溶解度参数,简化了溶解度参数的计算.20世纪80年代未,将此概念用到分散染料对PET聚酯纤维染色中去,通过计算,PET的δ为10.79,而传统PET的分散染料δ都在10.30～ 11.6之间,两者相容性很好,因此染色性能与牢度性能俱佳.将该方法引用到分散染料拼混和染厂拼色,可获得极佳效果.PTT聚酯的δ值为10.50,传统分散染料也适用它的染色.PLA纤维实际上是一类脂肪族聚酯纤维,性能与PET,PTT不同,它的δ值为12.8.显然使用传统分散染料达不到很好效果,亟待研究开发PLA专用分散染料.     

Dyeing from Solvents

With model dyes and chemicals, some basic physico-chemical phenomena of solvent dyeing are examined. Starting with properties of the solvents, different interactions between solvents and fibres, dyes and chemicals are described and the influence on the dyeing result is discussed. In conclusion, work on establishing solvent dyeing is considered as a stimulus to dyeing technology as a whole.     

A novel and eco-friendly approach for dyeing polyester fabrics by liquid disperse dyes treated with deep eutectic solvent

Disperse dyes do not contain water-soluble groups and are difficult to dissolve in water, so they cannot be directly formulated into dyeing liquor. In the current dyeing process, the solubility of disperse dyes is mainly improved by adding dispersants. However, dispersants are not absorbed by fibres and survive in the dyeing effluent, aggravating the pollution of water bodies and causing difficulties in treatment. Therefore, the development of a novel, eco-friendly dyeing approach is important to overcome these problems. Herein, for the purpose of improving the solubility of disperse dyes and reducing the dosage of dispersants, a deep eutectic solvent consisting of choline chloride/ethylene glycol was employed instead of dispersant to dissolve CI Disperse Blue 79 and CI Disperse Red 343, thus forming liquid disperse dyes. The results show that both CI Disperse Blue 79 and CI Disperse Red 343 were well dissolved in choline chloride/ethylene glycol with excellent stability, and the dissolution behaviour was strongly associated with the dissolution temperature and time. Moreover, polyester fabrics can be dyed successfully with liquid disperse dyes, and it was observed that the K/S value and rubbing fastness were evidently improved at the same dyeing temperature with unchanged colour characteristics, and a higher K/S value could still be obtained by lowering the dyeing temperature. This work establishes a green dyeing process, which reduces dyeing costs and meets the demand for environmental protection. It is also expected to realise the liquid state of disperse dyes, which will help to promote the further development of textile dyeing.     

Synthesis,spectral properties and dyeing on polyester of monoazo dyes from indol‐2‐one derivatives

Three series of phenylazo disperse dyes were prepared by coupling diazotised 4‐aniline dyes with 5‐indol‐2‐one dyes. The structures of these dyes were determined by proton nuclear magnetic resonance, Fourier Transform–infrared and elemental analysis. The effects of solvent on the ultraviolet–visible absorption spectra of these dyes were studied. The dyes displayed a λ_max shift of between 399 and 438 nm. The dyes were finally applied in the dyeing of polyester fibres in order to investigate their colour range and dyeing properties. Most of the dyes displayed high rubbing fastness and good washing and sublimation fastnesses on polyester fibres.     

A systematic study of dyeing polybutylene succinate fibres

Biodegradable polybutylene succinate (PBS) fibre is a new type of textile fibre, but its application in the textile industry is limited by the lack of related dyeing methods. In this study, the solubility parameters of PBS fibres are calculated, and solvent dyes with similar solubility parameters are proposed to dye PBS fibres to show that the dyeing scheme creatively resolves the difficulty in dyeing PBS fibres. The technical parameters of suitable dyes, and the dyeing conditions with ethanol as the dyeing medium, consisted of a dyeing temperature of 90°C, a dyeing time of 30 minutes and a liquor ratio of 30:1. The dyeing results show that the levelling property is good, the dyebath exhaustion is high, and the washing fastness, the rubbing fastness and the perspiration fastness index of the dyed fibres are satisfactory.     

The Development of Dyes and Methods for Dyeing Polyester

Early work on the dyeing of polyester fibre showed that only dyes of very low aqueous solubility had substantivity for the fibre, and that for dyeing at the boil without a carrier only the smallest molecular weight disperse dyes, and selected azoic combinations, had sufficiently high dyeing rate to give adequate colour yield in a practicable time of dyeing. The development of carriers for dyeing at the boil, and of machinery for batchwise dyeing under pressure at temperatues up to 140°C, extended the range of suitable dyes to those of lower dyeing rate but higher heat–fastness properties. As an alternative to exhaust dyeing, polyester may be dyed with disperse dyes by padding followed by dry heat fixation at temperatures up to 220°C, and this method has found its main commercial application in the continuous dyeing of polyester–cellulosic blend fabrics. The development of new disperse dyes has followed these trends in application methods, and the proportion of available dyes having higher heat–fastness properties has steadily increased from about 1950 onwards. Improvements have also taken place over the same period in the physical properties of the dyes, to meet the increasingly severe demands on dispersion properties imposed by the newer dyeing methods.     

The Use of Non-aqueous Solvents in Dyeing I - Dyeing Polyester Fibre by the Dacsol Process

The Dacsol process (J. & P. Coats Ltd) is a totally non-aqueous system designed principally for dyeing polyester fibre with existing disperse dyes, thus enabling fastness levels to be maintained. It is a bicomponent homogeneous system using perchloroethylene and a silicone fluid. Dyeing takes place in a pressurized dyeing machine at elevated temperatures and for times as low as 30 min. Residual solvent and surface dye are removed by rinsing with acetone, which facilitates steam drying. It is a dry-to-dry process. The dyeing and rinsing solvents are recovered by decolorizing with activated carbon and by distillation.     

The Dyeing of Polyester Textile Fabric in Perchloroethylene by the Exhaust Process

The dyeing behaviour of disperse dyes in perchloroethylene is considered. In particular, the relationship between distribution equilibrium and colour yield, the effect of auxiliary solvents on colour yield, the effect of water on the dyeing mechanism, the dependence of the colour yield on the amount of water and time and temperature of dyeing, and the effect of auxiliary solvents on the colour yield in water-containing perchloroethylene liquors are discussed. The stripping of dyes from polyester with trichloroethylene is mentioned. Finally, the selection of dyes for use in the dyeing of polyester from perchloroethylene by exhaust processes is considered. The desire for a solvent-based dyeing process can be fulfilled. Dyeing of polyester from perchloroethylene can offer a number of technical advantages which make it a genuine alternative process to the conventional dyeing methods.     

Relationship between the solubility of disperse dyes and the equilibrium dye adsorption in supercritical fluid dyeing

In order to understand the dyeing behaviour of synthetic fibres in supercritical carbon dioxide, the solubility of some disperse dyes in supercritical fluid, as well as the rate of dyeing and the equilibrium adsorption of these dyes, have been studied. Dye solubility was measured by a dynamic analytic method at a range of pressure (7.5–25 MPa) and temperature (50–145 °C). The apparent rate of dyeing was measured and the dyeing isotherm was obtained by plotting the equilibrium dye adsorption against the equilibrium dyebath concentration. Linear isotherms were obtained when poly(ethylene terephthalate) samples were dyed with the disperse dyes. The mechanism of dyeing using supercritical carbon dioxide was discussed by considering the solubility, the dyeing rate and the dyeing isotherm.     

Kinetics of solvent-assisted dyeing of acrylic fibres

The kinetics of dyeing acrylic fibres with cationic dyes in the presence of small amounts of the solvents ethylene carbonate, propylene carbonate, nitromethane and iso-amyl alcohol has been studied. The time of half-dyeing was taken as a measure of the rate of dyeing, which was found to decrease with increasing concentration of the solvent in the dyebath. A linear correlation was observed between the rate of dyeing and the change in glass transition temperature of the fibre.     

Diffusion of disperse dyes into super-microfibres

The disperse dyeing process for polyester fibres is complex. It is characterised by the diffusion-controlled sorption of dyes and depends on dye concentration, dyebath temperature, dye liquor flow rate and fibre count. Moreover, the dyeing properties of super-microfibres are also quite different from those of microfibres or conventional polyester fibres. In this paper the influence of dyebath temperature, initial dye concentration and fibre count on the diffusion coefficient and the sorption isotherms has been studied. The analysis of kinetic properties has been restricted to infinite dyebath conditions. All experimental results have been compared terms of fibre count and dyebath temperature.     

Textile applications of photochromic dyes. Part 5: application of commercial photochromic dyes to polyester fabric by a solvent‐based dyeing method

A series of commercial photochromic dyes was applied to polyester by a solvent dyeing process followed by thermal fixation using dichloromethane as the solvent. The process was optimised in terms of solvent/fabric ratio, dye concentration and the conditions of thermal fixation. The dyed fabrics showed reversible photochromism, developing colour on ultraviolet exposure and fading after removal of the ultraviolet source. The degree of photocoloration, background colours, fading characteristics, fatigue resistance and storage stability of the dyes were evaluated and comparisons made with the outcomes of a traditional aqueous disperse dyeing method. A study of the visible spectra of concentrated solutions of the dyes in a range of solvents provided evidence for the origin of the permanent background colours on the fabric when applied from solvents. Relationships were established between the magnitudes of the visible absorption in solution and the background colours developed, in relation to the nature of the solvents. The results suggest that toluene and ethyl acetate may offer certain advantages as solvents for the application of these dyes.     

A New Insight into the Thermofix Dyeing of Polyester-Cellulose Blends

Novel experimental techniques have been used to show that in thermofix dyeing disperse dyes are transferred from cotton to polyester fibres—in a blend or union fabric—solely by a vapour-phase mechanism. Other possible modes of transfer were examined, but no evidence was found to support them. The heat fastness of paniculate disperse dyes on cotton was correlated with their transfer properties to polyester fibres. The various types of behaviour of disperse dyes in bulk application are explained. Functions of padding assistants and, in particular, a migration inhibitor and the importance of time and temperature in thermofixation procedures are dealt with in practical terms in Part II of the paper.     

Dye Diffusion-The Key to Efficient Coloration

This paper was presented to the Manchester Region on 14 December 1978, and to the West Riding Region on 22 February 1979.More than any other factor, the rate and degree of diffusion of dyes into the individual fibres composing any textile substrate control the productivity, reproducibility and the quality (with respect to appearance and sometimes the fastness properties) attained in each process. Using direct (fibre cross–section) measurement of the degree of penetration of dyes into nylon, polyester and acrylic fibres, under a variety of application conditions, the relationships between dye penetration and visual colour yield has been determined with fibres differing in cross–sectional shape and delustrant content. The present interest in saving energy, time and water has led to numerous processes resulting in ‘ring–dyeing’. Batchwise dyeing for relatively short times or at somewhat abnormal temperatures, and continuous dyeing by rapid steam–fixation techniques are examples which have been investigated to define application conditions that might be expected to cause problems in bulk–scale production.     

新型化学纤维与染料的关系

介绍了涤纶超细纤维、Ｔｅｎｃｅｌ纤维及氨纶、锦纶等新型纤维的特点及其发展现状。通过对染色机理的分析,论述了适用于上述纤维的各类印染染料之特征。     

Azides Part I - Reactive Dyes Containing the Azido Group for Synthetic-polymer Fibres*

Dyes containing sulphonylazido, carbonylazido, arylazido and azidoacetamido groups have been synthesized. These dyes react chemically with synthetic-polymer fibres, such as polyester, nylon and cellulose acetate. Their dyeing and fastness properties are discussed.     

Report of the Committee on the Dyeing Properties of Disperse Dyes

Four tests are prescribed for assessing the dyeing properties of disperse dyes on polyester fibres. The tests for migration and build-up properties correspond essentially to those already developed for disperse dyes on other fibres. The critical temperature test classifies dyes in terms of relative rate of initial strike. The diffusion test is a simple means of comparing relative rates of penetration of dye into polyester. As with tests recommended in previous reports, these tests permit individual dyes to be rated on an A-E scale for each property, with the exception of the critical temperature test where an A-D scale is used.