New Approaches to Washfast Dyes for Wool:

Dyes incorporating β-isothioureidopropionamide and β-isnthioureidoethyl salt groups have been synthesized by reaction of the corresponding bromide or iodide with thiourea. Such dyes can be applied in the cationic form to wool and bask-dyeable fibres, and then, by raising the pH to 9–10, decomposed on the fibre to give fast dyeings. These dyes can also be successfully applied as disperse dyes to appropriate fibres by carrying out the decomposition before dyeing in the presence of dispersing agents. By a combination of these two systems, both components of wool polyester blends can be dyed with the same dye. The high washfastness of isothiouronium dyes on wool is thought to be due to insolubilization within the fibre rather than to mixed disulphide formation with cystine.     

毛用活性染料

本文对毛用活性染料的结构类型、发展史、Lanasol染料及其染色特点作了简要的概述.介绍了新开发的毛用活性系列染料,并将其与国外同类产品进行了应用性能对比测试.     

羊毛染色用酸性染料

酸性染料是含有负电荷基团的，如磺酸基等阴离子性染料。酸性染料的名称源于酸性浴的使用。鉴于磺酸基的强酸性，它在水中实际上是完全电离的。染浴中使用酸的范围从硫酸至醋酸铵盐，羊毛纤维吸收酸并使纤维的氨基质子化了。因此，染色过程包括了离子的交换过程，并在染浴中产生羊毛纤维上的铵离子与染料阴离子的结合。     

Photoreactive Dyes: The Potential of Azido-substituted Dyes as Latent Reactive Dyes for Wool

Dyes containing azido substituents have been examined as latent reactive dyes for wool and nylon. Three different substituents, viz. azidophenyl, azidosulphonyl and diazidotriazinyl, were used. It was found that dyes containing azidophenyl groups could be applied under conditions where little reaction with the fibre occurred. These dyes could then be induced to react covalently with the fibre either by irradiation with light or by ironing at 200d?C. However, the binding of the dye to the fibre occurs in rather low yield (30–40%) and, in some cases, is accompanied by a marked colour change. Dyes containing azidosulphonyl or diazidotriazinyl substituents react with wool and nylon during application, and they are therefore unsuitable as latent reactive dyes.     

2-Pyrazoline Dyes for Wool and Nylon

A range of yellow fluorescent 2-pyrazoline acid dyes has been synthesized. Their spectral and dyeing properties (on wool and nylon) depend both on the nature of the substitution pattern of the dye and on the nature of the fibre substrate. Exhaustion and fastness to washing, which are better on nylon than on wool, are improved by substituents attached to the 2-pyrazoline ring. Fastness to light is independent of the fibre and is increased by substituents on the 4- and 5- positions of the 2-pyrazoline ring. The fastness properties of the pyrazoline dyes were compared with those of C.I. Acid Yellow 7.     

Metal-complex Dyes for Wool and Nylon — 1930 to date

An introduction outlining the scope and limitations of this paper is followed by a brief explanation of the essential structural features of metal-complex dyes. The earliest metal-complex dyes were produced directly within the fibre material by reacting a metallisable dye with a chromium compound in situ. The first chromium complex dyes prepared in substance, were the chromium complexes containing sulpho-groups, synthesised by R Bohn of BASF, in 1912, the application of which was first made possible after the discovery by Ciba of a satisfactory dyeing process based on the use of a dyebath made strongly acid with sulphuric acid. These two classes of dye dominated the dyeing industry into the 1950s. At that time 1:2 metal-complex dyes without sulphonic acid groups but containing nonionic substituents as solubilising groups were introduced. These complexes were applicable from neutral to weakly acid dyebaths, which minimised the damage to the fibres. These dyeings were characterised by high fastness to light and wet treatments. Later, for commercial reasons, sulphonic acid groups were again introduced into the dye molecule to increase their hydrophilic properties. These dyes also have become well established as a result of the introduction of new dyeing methods and the development of dyeing auxiliaries designed to promote level dyeing. In addition to these types of metal-complex dyes, further metal-complex dyes selected from the extensive patent literature of the last 50 years because of their interesting structure are described.     

改性羊毛的染色性及染料的选择

比较了氯化改性和拉伸改性羊毛的染色性。氯化改性羊毛的上色速率、上染平衡比原毛快,各项色样牢度基本相同或略高;在拉伸羊毛的拉伸率较高时,其上染率和平衡上染率会明显提高;拉伸(不)定型和染色条件对染色性能有明显影响。选择了1:1金属络合染料、1:2金属络合染料和溴代丙烯酰类毛用活性染料对改性羊毛染色,探讨了染色机理,在两种改性羊毛达到了低温染色的要求,80℃时上染速度快、上染率高,能透染。     

改性羊毛的染色性及染料的选择

比较了氯化改性和拉伸改性羊毛的染色性。氯化改性羊毛的上色速率、上染平衡比原毛快,各项色样牢度基本相同或略高;在拉伸羊毛的拉伸率较高时,其上染率和平衡上染率会明显提高;拉伸(不)定型和染色条件对染色性能有明显影响。选择了1:1金属络合染料、1:2金属络合染料和溴代丙烯酰类毛用活性染料对改性羊毛染色,探讨了染色机理,在两种改性羊毛达到了低温染色的要求,80℃时上染速度快、上染率高,能透染。     

Application of Chrome Dyes to Wool by the Afterchrome Process

The fundamentals of and practical experience with a new method of applying chrome dyes to wool by the after–chrome process are discussed. The method is based on the stoichiometric relation between chromium and chrome dyes. By using special temperature control and an electrolyte, potassium dichromate is utilized more efficiently and effluent requirements can be met in most cases. The quality of the wool is improved compared to wool dyed by conventional afterchrome processes.     

The Coloration of Wool with Disperse Dyes

Work is described which shows that, by treating wool with certain amides, polyhydric alcohols or carboxylic acids, the affinity of the fibre for disperse dyes can be greatly enhanced. The most suitable compounds, with regard to effectiveness, price and commercial availability, are thiodiglycol and glycerol. Particular reference is made to the sublimation transfer-printing technique; the fibre is pretreated by pad-dry application of the compounds, and prints of excellent yield and clarity are obtained using standard disperse dye transfer papers. Yellowing and fibre damage during transfer printing are minimized by the inclusion of sulphamic acid in the pad-liquor. Wet-fastness properties of the prints are poor, but may be improved to a certain extent by the use of selected disperse dyes.     

Photoreactivity of Wool Dyed with Reactive Dyes

Presented at the 13th Congress of the International Federation of Associations of Textile Chemists and Colourists in London on 20 September 1984. Processes induced by two kinds of illumination (ultra-violet and Xenotest) in wool dyed with reactive dyes ha ve been investigated as a function of time. The fading of dyed fibres has been determined in terms of the conditions of illumination. The degradation of wool was followed on the basis of changes in alkali solubility and tensile characteristics. Moreo ver the colour change of the dyed fibres was also determined. Correlation was found between the chemical structure of the dye, the extent of fading and the photodegradation undergone by the wool. On the basis of amino acid analysis conclusions were drawn on the photodegradation mechanism of wool, both uncoloured and dyed with reactive dyes. Reactive dyes protect wool against photodegradation, and at the same time the light fastness of reactive dyes on wool is 1–1.5 units higher than on cotton, both under ultra-violet (u.v.) and Xenotest irradiation.     

Pad-Batch Dyeing of Wool with Reactive Dyes

A process for the production of fast, bright dyeings on wool cloth is described. Reactive dyes applied by a pad-batch (cold) method yield level dyeings with very high colour yields. Virtually 100% fixation has been obtained with Procion M (ICI) dyes applied to wool from mildly acidic solutions, after batching for up to 24 h at room temperature. Yellowing of wool does not occur under these conditions, which facilitate the production of dyeings of a brightness and fastness that cannot be achieved under conventional dyeing conditions for wool.     

毛用活性染料结构特性与清洁生产

本文主要介绍了毛用活性染料的结构特性,阐述了在生产毛用活性染料的过程中如何实现清洁生产。从毛用活性染料的结构特点为视角,讨论了今后清洁生产的发展方向,以及为了适应清洁生产,基础化工原料和毛用活性染料在未来的发展方向。     

Dyeing of Wool–Polyester Blends with Reactive Disperse Dyes: Variation of Dye Distribution and Reactivity for Wool

The dyeing behaviour of structural analogs of some commercial reactive disperse dyes on a simulated 70:30 wool–polyester blend has been studied. By varying the hydrophi/ic– hydrophobic balance of the dye molecule major changes in the distribution of dye between wool and polyester were observed. The reactivity of the γ–halo–β–hydroxypropyl group was found to be dependent on the halogen atom, while the reactivity of the N–bromoalkylsulphonamide group was found to be dependent on the position of the bromine atom.     

Exhaustion of Dyes on Wool at 105C

Laboratory trials have shown that many wool dyes are almost completely exhausted from the dye liquor after only 5 min at 105C, while the strength loss of the wool is no greater than in conventional dyeing methods. The uniformity of reactive dyeings under these conditions is reported.     

Sublimation Transfer Printing of Wool with Metallizable Dyes

The transfer printing of pretreated wool using sublimable dyes that form metal complexes on the fibre during printing is described. The most successful pretreatment involved padding a mixture of chromic chloride, an an ionic surfactant, urea and lactic acid and then drying. Low molecular-weight monoazo dyes containing salicylic acid residues, or hydroxyl or amino groups on carbon atoms in two ortho positions relative to the azo group, were screen printed onto transfer papers. Optimum heating conditions for transferring dye from paper to fabric were 200d?C for 30 s. After separation of the transfer paper, the fabric was steamed at 100d?C for 30 min. Prints with good fastness properties were obtained in a wide range of colours. The method offers promise for commercial transfer printing of pure wool fabric.     

Fixation on Wool of Dyes Containing a Maleimide Group

The chemistry of dyes containing a maleimide group is discussed. The mechanism of dye fixation on wool in depths greater than 1. 5% has been investigated. In samples which were dyed at pH 3, 80°C, little covalent reaction took place. Extraction with solvents, used to determine the fixation ratio, caused changes in the dye, as well as some further reaction, giving rise to apparently high fixation ratios. Dyeings on nylon fibre confirmed that covalent reaction of dye with amino groups is possible, especially between pH4 and 5. The best results in terms of fixation and yield were obtained in a dyeing procedure where the pHwas raised slowly during the dyeing.     

Fixation on Wool of Dyes Containing a Maleimide Group

A novel method has been developed for determining the fixation ratio on wool of dyes containing a maleimide group. Amino acid analyses are used to confirm that covalent reaction takes place when dyeing at the boil. This reaction, however, does not account for all the dye fixed on the fibre.     

Evaluation of Some Reactive Disperse Dyes for Sublimation Transfer Printing of Wool

The transfer printing of wool by the sublimation method using a number of low–molecular–weight dyes containing chloro– and bromo–acetyl, chloroacetamido, chloro– and bromo–propionamido, 2–bromoacryloyl, 2–chloroethylamino and epoxy groups has been examined. To achieve build–up of the dyes to heavy depths, it was necessary to pretreat the wool with a polymer or surfactant and to steam the prints after transfer of the designs. Several dyes exhibited good fastness properties on pure wool and on a wool–polyester blend fabric.     

Photoacoustic Spectroscopy for the Study of the Adsorption of Dyes on Wool Fabrics

Dyes have been applied to different wool fabrics and measurements by photoacoustic spectroscopy showed well-defined absorption bands. Differences were found in the spectral properties of dyes, which appeared visually to be very similar, indicating that photoacoustic spectroscopy may be useful for the identification of dyes on wool fabrics. Photoacoustic spectroscopy was also shown to be capable of measuring two-dye and three-dye combinations and very dark colours. Comparisons with reflectance spectroscopy showed that photoacoustic spectroscopy might usefully complement the results obtained from reflectance measurements.