Enzymatic hydrolysis of nylon 6 fiber using lipolytic enzyme

This study confirms the structural changes of nylon 6 fibers using lipase by measuring the dyeability, hydrophilicity, chemical changes, and fastness properties. For this purpose, nylon 6 fabrics were first treated separately with different concentrations of lipase enzyme. The dyeing process was then carried out on the treated fabrics with two disperse and acid dyes. A UV‐vis spectrophotometer was used for determination of dyebath exhaustion. Acid and disperse dyes showed higher dyebath exhaustion on the enzyme treated samples compared to raw material. The intensity of major peaks in FTIR spectra of the lipase treated samples are in favor of chemical changes of the polypeptide functional groups in fabric. Tensile strength of treated fabrics was decreased due to enzyme treatment. The results of color measurements in the CIELAB system showed that the darkness of the samples increased with an increase in the enzyme percentage in the solution. The results of moisture regain showed that treatment of nylon fabrics with lipolytic enzymes caused to increase the moisture absorbency. The wash and light fastness properties of samples were measured according to ISO 105‐CO5 and Daylight ISO 105‐BO1 and discussed. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Investigation into the effect of a plant‐derived stabiliser on the light and wash fastness of sulphur‐dyed cotton and nylon fabrics

In this study, cotton fabric and nylon fabric were dyed with a range of commercial sulphur dyes and the light and wash fastness of the coloured fabrics was investigated. The effect of after‐treating the coloured cotton and nylon fabrics with a tannin‐based commercial product, Bayprotect Cl, in the presence or absence of sodium sulphate in the treatment bath, was found to significantly improve the light fastness of the sulphur‐dyed cotton, and the photoprotective effect was partially stable to ISO 105‐C06 washing. In addition, the tannin‐based after‐treatment also improved the colour stability of the dyed fabrics to the perborate‐based ISO 105‐C06 washing. The possible mechanisms for the improved fastness properties are also discussed. The application of sulphur dyes to nylon is potentially commercially useful but has been limited because of the reported poor light fastness of the dyeings. The photoprotective effect of the tannin‐based after‐treatment was investigated with a view to providing the necessary commercial performance. However, it was established that on this fibre, the light fastness improvement was marginal, and the associated wash fastness to oxidative bleach‐based ISO 105‐C06 washing was limited.     

合成纤维及其混纺纤维用染料的研究 Ⅰ.用于锦纶染色的含β-羟乙基砜硫酸酯基活性分散染料

本文综合了应用于锦纶染色的弱酸性染料酸性浴上色的高竭染率,活性染料与纤维的共价键结合,分散染料在纤维上迁移、匀染、盖染性好等优点,提出一类含β-羟乙基砜硫酸酯基的活性分散染料。用分子较小的分散染料结构,以含β-羟乙基砜硫酸酯为活性基;在弱酸性浴中染色,再在弱碱性浴中与聚酰胺纤维反应成共价键结合。 合成了一系列偶氮型和蒽醌型染料。进行了合成工艺、对锦纶的染色性能以及染色锦纶的牢度等试验。并讨论了染料与聚酰胺纤维的结合 这类染料可用于锦纶66和锦纶6丝纺、弹力锦纶丝和针织品,还可用于桑丝、柞丝及其与人造丝的提花织物。这类染料在锦纶上色泽鲜艳,竭染率较高,益染性优良,耐晒、耐湿处理等牢度较好,适于各种锦纶织物的染色。这类活性分散染料,具有酸性染料、活性染料和分散染料染锦纶的主要特点。     

Study of physico-chemical surface treatments on dyeing properties of polyamides. Part 1: Effect of tetrafluoromethane low temperature plasma

Polyamide (nylon 6) fabrics have been treated with tetrafluoromethane low temperature plasma and then dyed with commercially available acid and disperse dyes. The morphology of the treated surfaces has been examined by scanning electron microscopy and chemical surface changes characterised by X-ray photoelectron spectroscopy. Dyeing results show that the plasma treatment slows down the rate of exhaustion but does not reduce the amount of absorption of acid dyes. The dyeing properties of disperse dyes on plasma-treated nylon fabrics changed markedly when compared with untreated fabric. A slight improvement in colour fastness is seen with the treated sample. The dyeing process has only a minor effect on the water-resistant surface, indicating that a stable surface has been achieved by the treatment. For Part 2 of this study, see page 31 of this issue of Coloration Technology.     

Aftertreatment of 1:2 metal complex acid dyes on conventional and microtibre nylon 6. 6 with a commercial syntan/cation system

Dyeings (2% owf) were produced on conventional and microfibre nylon 6. 6 fabrics using unsulphonated, monosulphonated and disulphonated 1:2 metal complex acid dyes. When subjected to the ISO 105:C06/C2 wash test, the wash fastness behaviour of the dyeings was related to the degree of sulphonation of the dyes. Aftertreatment of the dyeings using a commercial syntan improved the wash fastness of the dyeings whereas the sequential application of a cationic compound to the syntanned dyeings caused a further improvement in wash fastness.     

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.     

Organoclays assisted vat and disperse dyeing of poly(ethylene terephthalate) nanocomposite fabrics via melt spinning

Polyethylene terephthalate nanocomposites containing six modified montmorillonite nanoclays were prepared by a melt compounding technique. The effect of intercalated compounds of montmorillonite on textile mechanical properties of resultant polyethylene terephthalate nanocomposite fabrics was investigated. Winding was not possible, when the polymers were first compounded with the desired amount of montmorillonite and then spun, as filament breakage occurred. Spinable polymer were only obtained by mixing polyethylene terephthalate master batches with 4 wt% montmorillonite, which contained tallow intercalating compound with pure untreated polyethylene terephthalate to a montmorillonite content of 0.5 wt%, thus decreasing the concentration of thermally degraded polymer chains. After spinning the fibres were drawn and knitted into fabric samples for further testing. The prepared polyethylene terephthalate nanocomposite fabrics using montmorillonite exhibited higher colour strength using vat and disperse dyes compared with those of the reference fabrics made from fibres spun without montmorillonite clay content and regular fabrics. The carbocyclic‐based vat dyes have higher colour strength values on polyethylene terephthalate nanocomposite fabrics if compared with heterocyclic‐based vat dyes. The colour fastness ratings for both vat and disperse dyeings secured very good to excellent washing and perspiration fastness on polyethylene terephthalate nanocomposite fabrics. All dyed fabrics showed excellent light fastness using vat and disperse dyes. The preparation of polyethylene terephthalate nanocomposite fabrics with improved textile mechanical and vat dyeing properties needs further investigations.     

Dyeing Properties of Monoazo Disperse Dyes Containing 5- and 6-Aminoindazoles as Diazo Components

In this study the effects of various coupling components, used in conjunction with 5- and 6-aminoindazoles as diazo components, on the spectral characteristics and dyeing properties of dyes for cellulose secondary acetate (acetate), nylon 6 and polyester have been investigated. Eight new disperse dyes suitable for acetate, nylon 6 and polyester were synthesised. In general, when disperse dyes are applied in the dyeing of nylon 6 the colour fastness to water is very low. However, we found that the new dyes synthesised showed good dyeing properties in all cases, on all three fibre types. Some of the dyes obtained using 5- and 6-aminoindazoles gave bright dyeings of good fastness to light, washing, perspiration, dry cleaning and rubbing. Some bright dyeings on polyester were also obtained.     

Study of physico-chemical surface treatments on dyeing properties of polyamides. Part 2: Effect of UV excimer laser irradiation

Polyamide (nylon 6) fabrics were irradiated with a 193 nm argon fluoride excimer laser and the effects on the dyeing properties of the fabrics were studied. Chemical analysis indicated that carbonisation occurred in the laser-irradiated samples. The laser treatment breaks the long chain molecules of nylon, increasing the number of amine end-groups which change the dyeing properties of acid and disperse dyes. The results suggest that laser treatment could be used to improve the dyeing properties of nylon fabric with a disperse dye.     

Neutral dyeing of wool and wool/polyester blend fabrics using sulphatoethylsulphone reactive‐disperse dyes

Two models of temporarily anionic sulphatoethylsulphone reactive disperse dyes were applied to wool, polyester and wool/polyester blend fabrics at different dyeing pH. Maximum exhaustion values and colour yield were observed at pH 7. The results showed that reactive disperse dyes containing bis‐sulphatoethylsulphone reactive groups were more convenient for neutral dyeing of wool and wool/polyester blend fabrics if compared with a dye containing a mono‐sulphatoethylsulphone group. Excellent to very good wet fastness properties on all dyed fabrics were achieved.     

Dyeing and fastness properties of polyamide fabrics using some acid‐based monoazo disperse dyes

A series of monoazo disperse dyes derived from naphthalimide containing butyric acid has been applied on polyamide fabrics. The build up and dyeing properties of these dyes such as leveling property, wash, light, perspiration for alkaline and acidic conditions, and rubbing fastnesses on polyamide fabrics have been investigated. The results showed that the applied dyes are capable of producing red to bluish red hues on polyamide fabrics. Because of the presence of both carboxylic acid and hydroxyl groups on the molecular structure of Dye 3, it showed desired and more strength in respect to other used dyes. Comparing the build up of these dyes to commercial dyes such as disperse red 60 and disperse red 73 revealed that most of the used dyes have higher build up in comparison to the commercial ones. Measurement of fastness properties of dyed samples indicated that they have good wash (4–5), rubbing (4), perspiration (4–5), and heat fastnesses (4–5) and they possess less than moderate light fastness (3–4) on polyamide fabrics. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.     

Direct coloration of textiles with photochromic dyes. Part 1: Application of spiroindolinonaphthoxazines as disperse dyes to polyester,nylon and acrylic fabrics†

1,3,3‐Trimethylspiroindoline‐2,3′‐3H‐naphth[2,1‐b][1,4]oxazine ( 1a ) and 6′‐piperidino‐1,3,3‐trimethylspiroindoline‐2,3′‐3H‐naphth[2,1‐b][1,4]oxazine ( 1b ) were applied as disperse dyes to polyester, nylon and acrylic fabrics. Under optimised dyeing conditions, photochromic fabrics were produced which, on irradiation with ultraviolet or exposure to sunlight, turned blue ( 1a) or blueish‐purple ( 1b ). Dye 1a showed enhanced photochromic colour change performance compared with dye 1b . The photochromic colour build was highest on nylon and lowest on acrylic fabric. The colour change properties and the technical performance (wash fastness and photostability) of the photochromic fabrics were evaluated using specifically adapted colour measurement methods. The data were analysed in terms of variation of lightness, a*, b*, chroma, hue angle and ΔE, colour difference before and after exposure, and K/S curves as a function of irradiation time. The fabrics generally showed good wash fastness. Although the colour build‐up decreased with exposure to the Xenotest fadeometer, some residual photochromism remained after prolonged exposure.     

Extraction of polyphenolic dyes from henna,pomegranate rind,and Pterocarya fraxinifolia for nylon 6 dyeing

Acid and disperse dyes are two well‐known synthetic materials that are primarily used for dyeing of nylon 6 fibres. Despite their good performance, several negative impacts on the environment, including air and water pollution, are major concerns to researchers. An alternative ecofriendly approach to the dyeing of nylon 6 is the use of natural dyes, given their abundant natural sources, biocompatibility, biodegradability, non‐toxicity, non‐allergic responses, and non‐carcinogenic effects on human life. Based on these advantages, we extracted polyphenolic dyes from henna leaves, pomegranate rind, and Pterocarya fraxinifolia leaves and studied the dyeability on nylon 6 fabric using three compounds of aluminium sulfate, tannic acid, and tin chloride as toxic and non‐toxic mordants before dyeing. Fourier transform infrared spectra of the nylon 6 fabric confirmed the coordination complexes and π–π bonding between the mordants and the dyes. Colorimetric and fastness results showed that the mordants increased the colour strength and improved the fastness properties of the fibres. Our results suggest that tin chloride and aluminium sulfate as metal mordants can be successfully replaced with tannic acid as a biomordant in the natural dyeing of nylon 6. Also, cost assay showed that dyeing of nylon 6 with extracted natural dyes from waste leaves could be a sustainable and economical substitute for synthetic dyeing.     

Synthesis,spectral properties and application of novel disazo disperse dyes derived from polyester waste

Terephthalic dihydrazide was obtained through aminolytic depolymerisation of polyester bottle waste by using hydrazine hydrate. It was further reacted with 4‐aminobenzoic acid in the presence of polyphosphoric acid to obtain a cyclic compound, 4,4′‐[5,5′‐(1,4)‐phenylene)bis(1,3,4‐oxadiazole‐5,2‐diyl)dianiline, having a heterocyclic moiety. Diazotisation of this compound followed by coupling with various N,N‐disubstituted anilines afford a series of novel disazo disperse dyes. The structures of these synthesised dyes were confirmed by elemental analysis and Fourier Transform–infrared, proton nuclear magnetic resonance and mass spectroscopy. Ultraviolet–visible spectra of these azo dyes in different polar solvents showed considerable variation in the wavelength of maximum absorbance (λ_max). Application of these dyes on polyester and nylon fabrics using high‐temperature dyeing methods gave brilliant yellowish red hues with fair to moderate light fastness and very good to excellent wash fastness and sublimation fastness.     

Improving transfer printing and ultraviolet‐blocking properties of polyester‐based textiles using MCT‐β‐CD,chitosan and ethylenediamine

This study demonstrates the possibility of improving the transfer printability and fastness properties, as well as the ultraviolet‐protecting functionality, of polyester, polyester/wool, polyester/cotton and polyester/viscose woven fabrics via pretreatment with monochlorotriazinyl β‐cyclodextrin (MCT‐β‐CD), chitosan or ethylenediamine, followed by subsequent transfer printing with sublimable disperse dyes. The modification variables as well as the transfer printing conditions were optimised. The experimental results reveal that generating hydrophobic cavities (via grafting of β‐CD) at the fabric surface, fixing of chitosan, with its amino groups, onto the finish/fabric matrix, or introducing amine functional groups, via aminolysis of the polyester component, results in obtaining transfer printed fabric samples with darker depth of shades and better fastness properties, as well as with higher ultraviolet‐protecting functions. It was further noted that, in all cases, the enhancement in the imparted properties is governed by type of substrate, kind and extent of chemical modification, affinity for the sublimable disperse dyes, accessibility of generated hosting and fixing sites, as well as the ultraviolet‐blocking capacities of the modified/post‐printed substrates against damaging ultraviolet rays. The mode of interaction, as well as the surface morphology of some non‐treated and treated fabric samples, was also investigated.     

Ultrasonic‐assisted dyeing: I. Nylon dyeability with reactive dyes

The use of ultrasonic power (38.5 KHz, 350 W) to assist the dyeability of nylon‐6 fibre with reactive dyes is reported. The effects of the different factors that may affect the dyeability of nylon‐6 fibre with Reactive Red 55 were simultaneously carried out under both ultrasonic power and conventional heating conditions. The colour strength values obtained for the dyed samples using ultrasonic power were higher than those obtained using conventional heating. Also, the effect of alkaline soaping treatment on dye fixation for the dyed fabrics with different reactive dyes, at both acidic and neutral pHs, is generally better with ultrasonic than with conventional heating. The overall results indicate that the enhancing effect is mainly attributed to the de‐aggregation of dye molecules, which leads to better dye diffusion and possible assistance for dye‐fibre covalent‐bond fixation. The results of wet fastness properties of the dyed fabrics reveal improvement using ultrasonic power dyeing relative to the conventional heating method. © 2003 Society of Chemical Industry     

One‐step dyeing of polyethylene terephthalate fabric,combining pretreatment and dyeing using alkali‐stable disperse dyes

In the conventional dyeing process, polyester and its blended fabrics are usually dyed in a weak acidic medium. In order to reduce cost and improve production efficiency, a new dyeing method – one‐step dyeing of polyethylene terephthalate fabrics, combining pretreatment and dyeing in alkali conditions – was investigated. The alkali‐stable disperse dyes Red 900, Red 902, Yellow BROB and Blue 825 were used to dye polyethylene terephthalate fabrics. The dyeing properties of polyethylene terephthalate fabrics in the case of one‐step dyeing at various pH values or sodium hydroxide concentrations were discussed in terms of colour yield, colour parameters and fastness. The performance of one‐step dyeing using alkali‐stable disperse dyes was excellent. The dyed fabric had good fastness. Wet processing could be combined and shortened. One‐step dyeing of polyethylene terephthalate fabrics could reduce the consumption of water and energy and improve production efficiency. One‐step dyeing of polyethylene terephthalate has potential application in cleaner textile production.     

Dyeing of nylon 6 and silk fabrics with a model disulphide bis(ethylsulphone) reactive disperse dye

The synthesis of a new reactive disperse dye containing the disulphide bis(ethylsulphone) group is described. The dye has been applied to nylon 6 and silk fabrics at a variety of pH and temperature conditions. Optimum dye exhaustion and fixation were achieved at pH 8 and 130 °C. The results of dyeings on both substrates indicate that the model disulphide bis(ethylsulphone) reactive disperse dye shows a higher degree of exhaustion and fixation on silk than on nylon 6. The fastness and levelling properties on both fabrics were good.     

高分子染料在纤维染色中的研究进展

在纤维染色中,染料可以分为反应性高分子染料,分散高分子染料及酸性高分子染料等。这些染料具有各自鲜明的染色性能特点,如反应性高分子染料可与纤维以共价键结合而染色,分散性高分子染料与纤维有很好的相容性,酸性高分子染料可与相应的单体染料具有相同的染色性能但热稳定性更好。本文介绍了各类高分子染料的结构特点及在纤维染色中的应用情况。有24篇参考文献。     

Properties of differently printed and easy‐care finished linen fabrics

Linen fabrics were printed with reactive dyes, vat dyes and pigments. The prints were cured and after‐treated using conventional processes. Printed and unprinted fabrics were finished with low‐formaldehyde resin in a pad–dry–cure process. The mechanical properties (i.e. mass per unit area, flexural rigidity, tenacity at maximum load, wrinkle recovery angles and air permeability) with characteristics of printed and easy‐care finished fabrics were measured and the mutual influence of printing and finishing on these properties was discussed. Moreover, the colour difference between the finished and unfinished printed samples was measured, and the colour fastness to washing, appearance of fabrics after domestic washing, colour fastness to rubbing and light was compared.