Acetate dyes revisited: high fastness dyeing of cellulose diacetate and polyester—polyurethane

Colorants have been formulated from medium to high energy disperse dyes in an attempt to create dyestuffs for diacetate which not only meet existing toxicological regulations, but also build-up well and confer good wet fastness. Comparison of the performance of the formulations with that of conventional low energy disperse dyes, considered allergenic by Oeko-tex Standard 100, showed the former to have acceptable dyeability and superior fastness on 100% diacetate and an acetate-nylon mix. Some of the formulations also proved suitable for low temperature dyeing of a polyester-elastane blend, all furnishing dyeings with better wash fastness than that generally given by conventional polyester colorants.     

Effect of acylation on the dyeing and fastness properties of some azo dyes

The changes brought about by acetylation, benzoylation and terephthaloylation of some disperse dyes derived from 4–aminoazobenzene on the dyeing and fastness properties are described. Dyes substituted by benzoyl and terephthaloyl groups tended to have better light, wash and sublimation fastness on polyester. The dyes showed good build–up when these groups are coupled with an N–β–cyanoethyl group. Acylation of azo dyes resulted in poor substantivity and poor fastness properties on nylon 6.     

Improving light fastness of natural dyes on cotton yarn

The objectives of this study were to evaluate the light fastness of selected natural dyes (madder, weld and woad) and the effect of some commonly used antioxidants and UV absorbers on the light fastness of these dyes.

The photofading rate curves of madder and weld fixed on cotton correspond to type II fading rate curves described by Giles. These results are in concordance with those of Cox-Crews. The woad presents a type III fading rate curve, similar to the indigo fading rate curve presented by Cox-Crews.

A poor light fastness of the three natural dyes in comparison with synthetic ones is established beyond question. Nevertheless, the use of some additives can improve this default of natural dyes. In all the cases, the use of UV absorbers or antioxidants improved the light fastness of dyed fabrics. The most effectives were the vitamin C and the gallic acid.     

Colour fastness properties of alkali-clearable azo disperse dyes containing a fluoro-sulphonyl group

The colour fastness properties of alkali-clearable azo disperse dyes containing a fluorosulphonyl group have been investigated. In particular, the colour fastness properties of alkali-cleared poly(ethyleneterephthalate) were compared with those of conventional reduction-cleared poly(ethyleneterephthalate). Specifically, 4-aminoazobenzene dyes containing a nitro group in place of the fluorosulphonyl group in the 4'-position were synthesised in order to compare their fastness properties on poly(ethyleneterephthalate) with those of the 4'-fluorosulphonyl analogues.     

Colour gamut of natural dyes on cotton yarns

Cotton fibres were dyed using various natural dyes alone and in combination to yield six basic shades: blue, yellow, red, black, green and fawn. These dyed fibres were then blended in various proportions along with undyed cotton fibres and spun on a rotor-spinning machine to produce 204 coloured yarns. The fastness properties of the six basic shades were determined. The L * a * b * and L * C * h values of the yarns having 50% dyed fibre and 50% undyed cotton fibre was also determined. The values were plotted to obtain the colour gamut of natural dyes on cotton yarns.     

Reactive dyeing of cationized cotton: Effects on the dyeing yield and the fastness properties

The cationization of cotton fibers is emerging as an effective tool for solving the environmental problems associated with the dyeing of cotton fabrics with anionic dyes. In this study, the dyeing performance of cationizing agents (Rucomor Bur, Kemifix REA, Optifix F, and Optifix RSL) were examined, and we found that this method had better results compared with normal or existing methods of reactive dyeing. The dye‐bath exhaustion and fixation were determined by the help of an ultraviolet–visible absorbance spectrophotometer on the basis of the maximum absorbance wavelength. Better fixation values were found with the cationizing process than with salty dyeing. The washing and rubbing fastness results were as the same as those of traditional dyeing. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Polydopamine‐coated silk yarn for improving the light fastness of natural dyes

One of the problems occasionally associated with the use of natural dyes in the dyeing of silk is the susceptibility of the dyed yarn to fading in light. While a number of approaches have been used to address this problem, the use of polydopamine (PDA), a known agent with photo‐protective properties, has not been assessed previously. In this study, silk was pretreated with nano‐particulate PDA formed in situ by oxidation of a dopamine solution, then dyed with lac dye or annatto dye as model natural dyes. Photofading rates were significantly reduced in the case of annatto‐dyed, PDA‐coated silk relative to uncoated silk, while wash fastness was unaffected and remained only moderately good. In contrast, no significant change was seen in photofading rates with treated or untreated lac‐dyed silk, and wash fastness was also unaffected. The PDA did not adversely affect resultant colour values if the concentration of the dopamine precursor was kept low. When this was done, acceptable colours were obtained in the dyed silk. Further investigation is warranted of PDA as a photofading protectant and mordant with other natural dyes on silk and other fibres.     

PBT纤维染色牢度的研究

通过测试纤维的Lab值,比较纤维b值的不同,对比了PBT纤维与PET纤维的染色牢度,并进一步考察了空白PBT、PET纤维的被沾染的难易.结果显示：PBT纤维的色牢度好于PET纤维;PBT纤维比PET纤维容易被沾染;随着温度的升高,时间的延长,PBT纤维沾色越严重.     

Colour gamut produced by applying mixtures of natural dyes on de-inked mechanical pulp

Plants that are available from various regions of Greece were investigated as sources of natural dyes in a paper-dyeing operation. The production of natural dyes was achieved by aquatic extraction of plant materials in order to obtain an environmentally friendly method of producing the dyes. The extracted dyes were applied on de-inked mechanical pulp. A broad variation in shade and colour depth was achieved by applying mixtures of plant extracts in various combinations. The produced colours were found to lie in the first and second quadrant of a two-dimensional chromatic diagram.     

The colour and fastness of natural saffron

Cotton and wool fabrics have been dyed with the aqueous extract of saffron containing α-crocin as the main colorant species. The dyeings were carried out with and without metal salts as mordants. The wash and light fastness of the dyed fabrics was studied. The colour of the fabrics was investigated in terms of CIE L* C* H* values.     

Light fastness of naturally occurring anthraquinone dyes on nylon

Nylon fabric has been dyed with two purified components of Indian madder, purpurin (1,2,4-trihydroxyanthraquinone) and munjistin (1,3-dihydroxy-2-carboxyanthraquinone). The light and wash fastness of dyed and mordanted samples has been studied. Purpurin showed much better resistance to photofading than munjistin. It was found that the type of mordant and the method of mordanting significantly affected the rate and extent of photofading. The use of copper or ferrous sulphate gave high resistance to fading, whereas stannous chloride or alum did not. On the other hand, light fastness was improved when postmordanting was conducted with copper or ferrous iron, but pre-mordanting was superior in the case of stannous chloride or alum.     

Design of high fastness acid dyes for silk: a chemometric approach

A chemometric strategy tor the design of acid dyes for silk is reported. A small set of representative dyes was selected by the technique of fractional factorial design, using the principal properties of the substituents as design variables. The selected dyes were synthesised and fastness properties on silk were measured. Wash fastness and light fastness values were related to the chemical structure by the partial least squares (PLS) method. The models were used to predict the fastness of new dyes of the same class and to optimise the structure.     

Improvement of the light fastness of natural dyes: the action of singlet oxygen quenchers on the photofading of red carthamin

While the contribution of singlet oxygen quenchers to synthetic dyes has been investigated previously by several workers, there have been few studies pertaining to the use of singlet oxygen quenchers as a means of improving the light fastness of natural dyes. In this paper, the influence of various additives on the photofading of carthamin has been examined in cellulose acetate film. The rate of photofading of the colour was remarkably suppressed in the presence of nickel hydroxyarylsulphonates, while the addition of UV absorbers afforded little retardation in the rate of fading.     

2020年,全面复兴传统文化!

<正>2020年初,中共中央办公厅、国务院办公厅印发了《关于实施中华优秀传统文化传承发展工程的意见》(以下简称《意见》),并发出通知,要求各地区各部门结合实际认真贯彻落实。基本原则:《意见》指出:要牢牢把握社会主义先进文化前进方向;坚持以人民为中心的工作导向;坚持创造性转化和创新性发展;坚持交流互鉴、开放包容;坚持统筹协调、形成合力。总体目标:《意见》提出:到2025年,中华优秀传统文化传承发展体系基本形成,研究阐发、教育普及、保护传承、创     

New terpenoid dyes, 3-arylazocamphor derivatives: Dyeing performance and fastness properties

The 3-arylazocamphor (I–VI) and 3-arylazocamphor-2-oxime (VII–XI) dyes were prepared, for use as azodisperse dyes by coupling camphor or camphoroxime respectively with the appropriate diazonium salt in cold ethanol containing sodium acetate solution (10%). The structure of these compounds (I–XI) was established by studying their elemental analysis, i.r. and u.v. spectra. The effect of the nature and position of substituent in the arylazo moiety on the colour, dyeing behaviour, rate of exhaustion and fastness properties when applied to protein and man-made fibres were discussed. The effect of after-treatment with different metal salts on the dyed woollen fibre was also investigated.     

Diffusion of dyes in adsorptive dyeing

The concentration dependence derived from both steady-state permeation and unsteady-state dyeing runs for a system of acid dye C. I. Acid Blue 182-nylon 6 film was analyzed in terms of parallel diffusion with simultaneous multimodal adsorption proposed in the previous paper. The present dyeing process was governed by the surface diffusion incorporating three kinds of Langmuirean adsorption modes. The concentration dependence of the diffusion coefficient of the cationic dye C. I. Basic Red 22 in the anionically modified polyester fiber Dilana measured by Ostrowska et al. [B. Ostrowska, A. Narebska, and H. Krzystek, J. Appl. Polym. Sci., 26 , 463 (1981)] was satisfactorily interpreted by the parallel diffusion incorporating two kinds of Langmuirean adsorption modes.     

Application of rare earth as mordant for the dyeing of ramie fabrics with natural dyes

Selecting appropriate metallic compounds as mordants is essential for dyeing with natural dyes. This paper presents the application of rare earth compounds as mordant for the dyeing of ramie fabrics with four kinds of natural dyes. The influences of pre-mordanting, simultaneous mordanting, and post-mordanting on the dyeing effect were explored. The post-mordanting was proved to give rise to the highest dye uptake. The effects of dyeing conditions including dyeing temperature and time, dyeing bath pH and the concentration of rare earth on the dye uptake were investigated systematically. The fabrics dyed with natural dyes in presence of rare earth as mordant exhibited high color shade stability in the baths with pH varying from being acidic to neutral and alkaline. Employing rare earth as mordant apparently raised the color fastness to washing, rubbing and light of the ramie fabrics dyed with the natural extracts. In comparison with the commonly used metallic salts, using rare earth chlorides as mordants can greatly reduce the ionic concentration employed in natural dyeing. This study proved that rare earth would be a kind or promising environmentally friendly mordant in natural dyeing.     

Extraction of natural dyes from Alpinia blepharocalyx K. Schum. for dyeing of silk fabric

Natural dyes were extracted from the leaves and stems of Alpinia blepharocalyx K. Schum. Analysis of the designed experiment revealed that extraction at a plant/water ratio of 1:20 could reach an optimal production of natural dyes when extraction was performed at 80 °C, for 4 h, under 20 min ultrasound, in the presence of 10 g/l sodium hydroxide, and with two extractions. The extracted natural dyes were applied to the dyeing of silk fabrics using different methods, including or excluding a mordant. It was found that mordants had a significant effect on the colour of dyed silk fabrics. The silk fabric dyed with the pre‐mordant method using potassium aluminium sulphate as a mordant showed a bright yellow with a higher colour strength. The optimal dyeing conditions were reached when the extracted natural dyes were pre‐mordanted with 10 g/l potassium aluminium sulphate at pH 6, and for a 20 min dyeing time.     

Novel methods for dyeing the epidermis of bamboo culms and their colour fastness

This study examined the effects of various dyestuffs and treatment conditions on the epidermis colour of ma bamboo (Dendrocalamus latiflorus), moso bamboo (Phyllostachys pubescens), and makino bamboo (P. makinoi). The objective was to determine the optimum approach for endowing the bamboo culms with a fascinating brown colour without removing their epidermis, which would increase the economic value of bamboo products. Experimental results revealed that an excellent brown colour was obtained when bamboo culms were treated with 0.25% CI Basic Brown 4 solution in an 80 °C water bath for 60 min (H° values of 37.9, 25.0, and 25.7° respectively). In addition, alkali‐pretreated bamboo culms also exhibited a good brown colour dyeing when treated with 0.25% CI Basic Brown 4 at ambient temperature for 2 days (a* and b* values of 30.8 and 35.1 respectively). Furthermore, the use of an ultrasonic bath instead of a water bath can reduce the treatment time required for achieving an improvement in the effectiveness of brown colour dyeing of the bamboo epidermis. Results obtained from indoor light fastness tests demonstrated that more uniform dyeing and better colour fastness could be achieved by colour fixation post‐treatment with 1% glacial acetic acid.