Union Dyeing Research Articles

High union dyeing and fixation rate of cotton/modal blended fabrics via union dyeing with fiber swelling agents

High union dyeing and fixation rate of cotton/modal blended fabrics via union dyeing with fiber swelling agents

Union Dyeing of Cotton-Silk Blended Woven Fabric Using Tanin Bio-mordant and Thyme as a Colourant

The study explores the application of tea leaf-extracted tannin as a bio-mordant and thyme extract as a natural dye on cationized silk-cotton blend fabric to enhance colour fastness and absorption. The colour strength and depth (shown as DL, Da, and Db values) on silk-cotton blend fabric were investigated in the CIE lab test. The results showed that temperature, shade percentage, and mordanting had a substantial impact on the dyeing process efficacy at DL = 30.61, Da = 11.49 and Db = 12.77. When the temperature was raised to 90 °C and the dye content was increased to 120%, the dyed sample's colour fastness (as measured by wash, rubbing, and perspiration) significantly improved, acquiring a grade of 4 to 5, which indicates good to excellent. There was a slight change in wet rubbing fastness from grade 3 to grade 4, indicating good to fair. The K/S values of the silk and cotton fibres, which ranged from 8.89 to 7.94 on average, respectively, demonstrated that the processes of bio-mordanting and cationization enhanced the absorption of dye. Tensile strength and extension increased in the weft direction to 22.19 N force and 5.21% extension at break, while the warp direction showed a fall to 6.63 N force and a rise in extension of 0.72%. FTIR spectroscopy confirmed the presence of Amino (N-H) bonds, Carbohydrate bonds (CH), Tannins, and Terpenoid phytochemicals of thyme in the dyed sample. The study highlights the potential of thyme extract as a natural dye and its benefits in improving the dyeing properties of silk-cotton blend fabric.

Study on enhancing the union dyeing of cotton/modal blended fabrics with cationic modifier

AbstractCotton/modal blended fabrics are favoured by the market because not only do they have the advantages of the dimensional stability of cotton and drape wear resistance of modal, they also overcome their shortcomings, displaying a sense of stiffness and smooth feel. However, because of the differences in the physical and chemical properties between each component, the dyeing of blended fabrics with reactive dyes is prone to problems such as low fixation percentage, different dyeing percentages and colour depth. Here, two cationic modifiers, 2,3‐epoxypropyltrimethyl ammonium chloride (GTA) and methaacryloyloxyethyltrimethyl ammonium chloride (DMC), were applied for cationic modification of cotton/modal blended fabrics, and their role in the dyeability and union dyeing of cotton/modal blended fabrics was studied. The results showed that the K/S and fixation percentage of the blended fabric treated with GTA and DMC cationic agents could be significantly improved compared with the control group, and that the colour fastness of the blended fabric can reach grade 4‐5. Compared with GTA, DMC‐modified cotton/modal blended fabric showed better union dyeing properties because of its better diffusion performance in the fibre. The mesoporous volume of the cotton fibre is higher than that of the modal fibre, while the micropore volume is the opposite. Consequently, DMC macromolecules, through free radical graft polymerisation, were more likely to diffuse into cotton fibres with more mesoporous content, increased the interaction force between anionic reactive dye and cotton fibre, and improved the dyeability of the cotton component and the union dyeing performance of the blended fabric.

A feasible approach for enhancing union dyeing of wool/acrylic blend fabrics with heterobifunctional cationic reactive dyes

In this work, a facile method to enhance union dyeing with cationic reactive dyes on wool/acrylic blend fabrics was reported. Three cationic reactive dyes containing various numbers of reactive groups were synthesized and employed on wool, acrylic and wool/acrylic blend fabrics using the one-bath one-step method. Factors affecting the dye exhaustion, union dyeing and leveling properties, including dyeing pH, temperature and dye structure, were investigated. Experimental results revealed that the cationic reactive dye containing heterobifunctional reactive groups and a cationic group attached on the backbone of structure exhibited better union dyeing properties, irrespective of dyeing method. The improvement in the union dyeing on wool and acrylic fabrics followed a decreasing order: Dye 1 > Dye 3 > Dye 2. In additional, the wool/acrylic blend fabrics dyed with Dye 1 showed outstanding leveling properties. The fastness properties of wool/acrylic fabrics for all cationic reactive dyes were good to excellent.

One-Bath Union Dyeing of Wool/Acrylic Blend Fabric with Cationic Reactive Dyes Based on Azobenzene

Three unreported cationic reactive dyes based on azobenzene were synthesized using a novel synthetic route. Synthesized dyestuffs containing three primary color dyes were characterized by FTIR, H-NMR, LC-MS, Element Analysis and UV-vis spectroscopic techniques. The absorption spectra of dyes were measured in three solvents with different polarities. The dyeing and color fastness properties of three cationic reactive dyes on wool, acrylic and wool/acrylic blend fabrics were determined. The optimum pH for wool and acrylic fabrics were 6 and 5, respectively. Effect of temperature, time on dyeing properties and color fastness properties on wool fabric showed the same tendency with acrylic fabric. The K/S value of wool fabric dyed with three dyes was similar to that of acrylic fabric when both fabrics were dyed simultaneously in the same dyebath using low dye concentration. Wool/acrylic blend fabric dyed with three cationic reactive dyes using onebath one-step method achieved good union dyeing property and excellent color fastness.

Union dyeing of cotton/nylon blended fabric by plasma-nano chitosan treatment

AbstractCurrent union dyeing processes rely on one or two dye baths with one or two dyes for cotton/nylon blend fabrics. For 50:50 cotton/nylon fabrics, cotton is dyed first under alkaline condition with reactive dyes and then the nylon is dyed with acid dyes under acidic condition. Atmospheric plasma- nano Chitosan treatment as an environmentally friendly method was employed to modify surface properties of cotton/nylon blend fabrics to develop union dyeing with acid dyes. Cellulose fibers when immersed in water produce a negative electro-kinetic potential. The negative charge on the fiber repels the anionic dye ions and consequently the exhaustion of the dye bath is limited. When the fabric is treated with chitosan, the primary hydroxyl groups of cellulose is partially modified into amide groups, which intern leads the cellulose to act like as polyamide fiber. Experimental work was carried out on finding the possibility of one bath dyeing of plasma- chitosan pretreated cotton/nylon fabric with acid dyes. Plasma treated cotton/nylon surface characteristics were evaluated using FTIR. The surface activation using air plasma introduces different functional groups in cotton/nylon blend fabric. The effect of plasma-nano chitosan pretreatment on dye ability, fastness, and few physicochemical properties has been investigated, and results are presented. The cotton/nylon sample treated with 0.3% of chitosan nanoparticles had higher K/S values, washing, and crocking fastness. New method of union dyeing showed good fastness properties and offers the option of eco-friendly.

Union Dyeing of Wool/Polyester Blend Fabric Using Sulphatoethylsulphone Dye Derivative of C.I. Disperse Yellow 23

This paper aims to synthesise, characterise and find out the properties of a model dye for convenient union dyeing of wool, polyester and wool/polyester blend fabric compared with C.I. Disperse Yellow 23. The reactive disperse dye was prepared containing sulphatoethylsulphone (SES) as a reactive group. The dye was synthesised by diazotization and coupling reaction. Firstly, we synthesized azo dye intermediate I using 1-aminobenzene-4-sulphatoethylsulphone diazotized and then coupled it with aniline. The synthesized azo dye intermediate I was diazotized and coupled with phenol to give dye 2. Different factors affecting the dyeability and fastness properties of SES dye 2 were thoroughly investigated on wool, polyester and wool/polyester blend fabrics in comparison with C.I. Disperse Yellow 23 dye 1. Maximum exhaustion and total fixation yield using sulphatoethylsulphone (SES) dye 2 were achieved on wool fabric at neutral pH 7. The dye showed high dyeing performance due to its nonionic reactive VS derivative. The dyeing results indicate high quality dyeing properties

Synthesis and Application of Novel Reactive Disperse Dye Based on Tetrahydrobenzo[b] Thiophene Moiety

Ethyl 2-diazo-4, 5, 6, 7-tetrahydrobenzo[b] thiophene-3-carboxylate is reacted with malononitrile to give a hydrazone derivative. The latter product is reacted with 1-diazobenzene-4-β-sulphatoethylsulphone (PABSES) to give a disperse dye. The dye is synthesised by diazotisation and coupling reactions. First, it is synthesised with the chromophoric moiety of ethyl 2-hydrazomalononitrilo-4,5,6,7-tetrahydrobenzo[b] thiopheen- 3-carboxylate and coupled with diazonium salts that have the aforementioned reactive groups, thus yielding the new target reactive. The synthesised dye is applied onto wool, polyester and wool-polyester (blend) fabrics under typical exhaust dyeing conditions and their dyeing properties are investigated. The structure of this dye is characterised and confirmed by melting point, elemental analysis, infrared, ultraviolet-visible spectroscopy (UV/VIS) and nuclear magnetic resonance (1H-NMR) data. The dyeing of polyester, wool and polyester/wool blend fabrics with a reactive disperse dye gives very good build up and fastness properties by using a nonionic vinylsulphone (VS) derivative, which increases the substantivity of the dye towards wool fabric. Maximum exhaustion as well as total fixation efficiency by using a sulfatoethylsulfone (SES)-based dye on wool fabric is achieved at a neutral pH of 7. This feature of the dye structure significantly improves the union dyeing of wool/polyester blend fabrics with very good build up and fastness properties.

Union Dyeing of Wool/Silk Blends at Low Temperature

Protein fibers are attractive topics in the past decades. Among them, silk and wool fibers are very popular due to their luster, smooth surface and comfort. In order to reach union dyeing of silk/wool blends, chlorination pretreatment or introduction of low-temperature dyeing auxiliary for wool are selected and compared. The results showed that chlorination pretreated wool/silk dyed with weak acid dyes, can reach union dyeing under 80 oC, possibly under 70 oC. On the other hand, introduction of low-temperature dyeing auxiliary can slightly improve the union dyeing at different temperature ranges according to selection of weak acid dyes.

Union Dyeing of Soybean Protein Fiber/Wool Blends

Protein fibers are attractive topics in the past decades. Among them, soybean protein fiber, the regenerated protein-base fiber, is very popular due to its luster, smooth surface, breathability, and comfort. In order to blend with wool and reach union dyeing, soybean protein fiber was first bleached due to its yellow appearance. Various bleaching processes were introduced in this paper. Reactive dyes for cellulose and for wool, such as Unisol or Megafix dyes, together with proper dyeing process were selected and compared. The results showed that one-time oxidation bleaching is confirmed as the bleaching process due to its compromise of high whiteness and bursting strength. It is unable to reach union dyeing for soybean protein fiber/wool fiber with Unisol or Megafix dyes respectively while it is feasible to reach union dyeing of soybean protein fiber/wool fiber dyeing with Unisol dyes followed by Megafix dyes.

UNION DYEING OF WOOL/POLYESTER BLEND FABRIC USING A SULPHATOETHYLSULPHONE DYE ANALOGUE OF C.I. DISPERSE YELLOW 16

Dyeing of wool, polyester and wool/polyester blend fabrics with a sulphatoethylsuphone dye analogue of the commercial C. I. Disperse Yellow 16were investigated. Maximum exhaustion values and colour yield were observed using the modified disperse dye at pH 7. The result showed that the modified disperse dye was more convenient for union dyeing of wool/polyester blend fabric compared with the commercial disperse dye. Excellent to very good wet fastness properties on all dyed fabrics were achieved using the modified disperse dye if compared with the commercial disperse dye.

One‐bath union dyeing of a modified wool/acrylic blend with acid and reactive dyes

Pretreated wool/acrylic fibre was obtained by a facile amidoximation process. Fibre characterisation (nitrogen content, tensile strength, shrinkage, infrared spectra and X‐ray diffraction) proved the success of the pretreatment. Union dyeing of wool/acrylic fabrics with acid and reactive dyes, namely CI Acid Red 40, CI Acid Blue 25, CI Reactive Red 194 and CI Reactive Blue 25, was obtained using a one‐bath dyeing process. Different factors that may affect the dyeability of the blend fibre, such as dyebath pH, liquor ratio, temperature, time and dye concentration, were evaluated with respect to the dye exhaustion, fixation, colour strength, levelling and fastness properties. Excellent to good fastness was obtained for all samples, irrespective of the dye used. The result of the investigation offers a new viable method for union dyeing of wool/acrylic fibres in a one‐dyebath process.

Union dyeing of the photografted PET/wool blend fabrics with dimethylaminopropyl methacrylamide

Dimethylaminopropyl methacrylamide (DMAPMA) was grafted onto PET/wool blend fabrics by continuous UV irradiation. Union dyeing of the photografted fabrics was investigated using three reactive dyes of α-bromoacrylamide reactive groups. The influence of grafting yield, DMAPMA concentration, NaCl amount, pH value, and dyeing temperature on the dyeability was evaluated. The dyeability of both PET and wool components was improved significantly by the DMAPMA photografting and successive reactive dyeing. Although the dyeability of the PET component in the blend substantially was improved with higher grafting, equal dyeability between PET and wool was difficult to achieve due to more facile grafting and higher reactivity of the wool component compared with the modified PET component. However, the color fastness of the PET/wool blend fabric was excellent for all three colors. This study may offer a way to achieve union dyeing of PET/wool blend fabrics.

One‐bath union dyeing of wool/polytrimethylene terephthalate blends†

The one‐bath dyeing of blends of polytrimethylene terephthalate (PTT) staple and wool has been investigated. The exhaustion of selected Terasil disperse dyes on PTT fibre and Lanasol reactive dyes on wool was measured as a function of temperature, together with the cross‐staining of the Terasil dyes on the wool component and the Lanasol dyes on PTT component. Most Terasil disperse dyes achieved satisfactory dye uptake on PTT at 110 °C, whereas on conventional polyester (polyethylene terephthalate) temperatures of up to 130 °C are required. An optimised union‐dyeing technique for wool/PTT blends was developed which minimised the staining of Terasil disperse dyes on wool and produced dyed goods with high levels of wet colour fastness. Carriers were not required to enhance the dyeability of PTT at low temperatures. The wool component appeared to be protected against damage at 110 °C by the reactive dyes. The results indicate the potential for blending PTT fibre and wool to produce fabrics that are easier to dye at lower temperatures than conventional wool/polyester blends.

Union Dyeing of Easy Care-Finished Wool/Viscose and Cotton/Wool Blends

ABSTRACT Wool/viscose (60/40) and cotton/wool (70/30) blended fabrics have been easy-care finished in the presence of certain nitrogenous additives to produce readily dyeable cationic cellulose for competitive dyeing with wool dyes. The enhancement of easy care properties and improvement in post-dyeing of the finished fabrics were determined by the nature of substrate (wool/viscose > cotton/wool), type of catalyst (ammonium persulfate > ammonium sulfate > ammonium chloride > none), the kind of nitrogenous additive, as well as the type of polyethylene glycol (PEG-400 > PEG-200 > NONE). Using triethanolamine hydrochloride as a reactive/nitrogenous additive (30 g/L) in the finishing formulation as well as curing at 150°C/3 min make it possible to attain higher fabric resiliency along with better dye receptivity, regardless of the used anionic dye. However, the change in dyeing and fastness properties of obtained dyeing is governed by the nature of the anionic dye.

The use of sodium edate in dyeing: II. Union dyeing of cotton/wool blend with hetero bi-functional reactive dyes

Union dyeing of cotton/wool blend with hetero bi-functional reactive dyes, namely CI Reactive Yellow 145, CI Reactive Red 194, and CI Reactive Red 195 is obtained using one-bath and two-bath dyeing processes. The results obtained are compared with those obtained by conventional two-bath dyeing process. Factors affecting the dyeability, such as the amount of sodium edate, sodium sulphate, temperature and dye concentration are investigated. The dyed fabrics were evaluated with respect to the dye exhaustion and fixation, levelling and the fastness properties. Excellent to good fastness was obtained for all samples irrespective of the dyeing method. The result of investigation offers a new viable method for union dyeing by using sodium edate two-bath and one-bath processes with a better levelling and dye uptake.

Microscopical Investigation of Cotton Chemically Modified to Accept Wool Dyes for Wool/Cotton Blend Textiles

Abstract Renewed interest in textile blends of wool and cotton has led to developments in union dyeing (same shade on both wool and cotton fibers) that has potential for increased markets for both fibers as trans-seasonal apparel. The difficulty of efficiently dyeing wool and cotton to the same shade has limited the availability of yarns and fabrics containing blends of both fibers. In fabrics containing blends of cellulosic cotton and proteinaceous wool, it is generally necessary to employ more than one class of dyes and the process involves several steps with adjustments of pH and temperature. The ARS process provides maximum effectiveness and efficiency for one-step union dyeing. It requires pretreatment before dyeing to impart cationic character to cellulosic cotton so that it can compete with protonated wool for a common anionic dye. Three pre-treatments have been applied.

The Union Dyeing of Acrilan‐Wool Blends

Early methods of dyeing Acrilan–wool blends in solid, shades are outlined and the limitations stated. A new method is described which is applicable to all classes of wool dyes. Data are presented to show how the concentration of sulphuric acid and of a cation‐active dyeing assistant may be varied to control the relative dyeing rates of wool and of Acrilan and the migration of dye from wool to the Aerilan acrylic fibre to produce solid shades.

Studies on Union Dyeing of Acetate/and Viscose/Blended Fabrics

Studies on Union Dyeing of Acetate/and Viscose/Blended Fabrics

The Distribution of Direct Dyes between Wool and Cotton in One–bath Union Dyeing Part

Durazol Red 2B shows maximum affinity for cotton at 40°c., but is absorbed more rapidly at higher temperatures; on wool both the rate of absorption and the amount of dye absorbed increase as the temperature is raised. The effects of adding Glauber's salt to the dyebath, and of varying the liquor–goods ratio, are very similar for both wool and cotton. Addition of small amounts of acid to the dyebath greatly increases the amount of dye absorbed by the wool, but the absorption by cotton is relatively insensitive to pH changes. Provided that acid is not present, the percentage exhaustion of a union dyebath is low, except when the amount of dye available is small.When only a small amount of dye is used, the eolour of the two fibres is the same when each contains the same amount of dye. As the percentage of dye on the fibre increases more dye is required on the cotton than on the wool if the shades on the two fibres are to match. Ultimately, the amount of dye required on the cotton may be four times as much as that required on the wool. The maximum depth of shade obtainable on cotton is much less than that obtainable on wool.