Vinylsulphone Reactive Dyes Research Articles

Development of batik design on mulberry silk waste / wool blended fabric using vinyl sulphone reactive dyes

The study attempts to rematerialize the traditional art of Batik by studying the results obtained on mulberry silk and wool blended fabric. The objectives were to study the art of batik in detail and explore the possibilities of batik design development on mulberry silk/wool blended fabric with vinyl sulphone reactive dye (Cold reactive dyes). Dyeing time, pH, and dye concentration were optimized for the dye and designs were prepared by use of batik method. Optical density of the dye solution was studied to determine the absorbency of dye from the dye solution at different pH, time, and dye concentration. CIE Lab and K/S values were also assessed for determining the optimum dyeing conditions. Good results were achieved when designs were developed and the dyed samples exhibited fair to good wash, light and perspiration fastness.

Dye fixation and decolourization of vinyl sulphone reactive dyes by using dicyanidiamide fixer in the presence of ferric chloride

A synthetic polymer was synthesized and used for the improvement of dyeing properties as well as decolorization of textile waste water. Two dyes were selected having anthraquinone based Remazol Blue R and azo based Remazol Red RB. It was observed that the synthetic polymer can be used as fixer for the fixation of dye by crosslinking between dye and fibre, which not only improves the dyeing properties but also helpful to coagulate the colour after dyeing. By single point method the concentrations of synthetic polymer were calculated in residual after dyeing. It was examined that the residual synthetic polymer is helpful in colour removal efficiency by coagulation of polymer with dye to form heavy molecules which settle down and decolorization occurred. Colour removal efficiency was found dependents on pH, concentration of synthetic polymer and inorganic coagulant.

Decolorisation of Remazol vinyl sulphone reactive dyes by potassium permanganate

Three Remazol vinyl sulphone-based reactive dyes were selected to investigate their decolorisation by potassium permanganate, in relation to pH, concentration of potassium permanganate and time. The amount of colour removal was measured by ultraviolet–visual spectrometry and it was found that potassium permanganate only partially degraded the dye solution; this was also proved by the percent removal of chemical oxygen demand and total organic carbon. Decolorisation was observed to increase when the pH of the dye solution was decreased. Up to a pH level of 5, the decolorisation efficiency is very much slower, but as the pH level shifts towards 2 the rate of decolorisation becomes relatively faster, while a further decrease in pH results in a rapid change in decolorisation. The concentration of potassium permanganate also showed significant effects on the decolorisation. Rapid decolorisation was observed within 10 min for all three dyes, but after that time the decolorisation became slower.

Reactive dyeing of a pretreated jute fabric using minimum application technology

Grey jute fabrics were given pretreatment such as scouring which was followed by enzyme treatment. These pretreated jute fabrics were subsequently bleached with hydrogen peroxide. Dyeing of these bleached jute fabrics was carried out with four different classes of reactive dyes, namely cold- brand, hot-brand, vinyl sulphone and HE-brand reactive dyes, following the conventional exhaust method and pad-batch method, i.e. minimum application technology method. With respect to dyeing behaviour, it was found that dye uptake and wash fastness property of a dyed fabric produced by the pad-batch method is well comparable with that produced by the conventional exhaust method. Irrespective of the methods of dyeing, scoured–bleached and scoured–enzyme treated–bleached jute fabrics show better dye uptake and fastness property compared to grey-bleached fabrics. Weight loss and strength loss increase while bending length decreases with the increase in pretreatment stages. Enzyme treatment of a scoured jute fabric before bleaching produces the minimum bending length among all the samples. The pretreatment process is found to have some detrimental effect on the tensile properties of a jute fabric and as the number of pretreatment steps increases, the tenacity of the fabric decreases. Reactive dyeing of pretreated jute fabrics further reduces their tensile strength by around 10% irrespective of the method of dyeing and the pretreatment process. So, minimum application technology can be well adopted for dyeing of a jute fabric with reactive dyes. The process is simple, cost effective as it utilises dye to its maximum extent, requires minimum energy and is suitable for use in cottage and small-scale industries.

Reactive dye decolorization using combined ultrasound/H 2O 2

The decolorization of six vinylsulphone reactive dyes (C.I. Reactive Yellow 15, C.I. Reactive Red 22, C.I. Reactive Blue 28, Remazol Dark Black N 150%, C.I. Reactive Blue 220 and C.I. Reactive Black 5) in aqueous solution was investigated using ultrasound and ultrasound/ hydrogen peroxide degradation. Two different concentration levels of hydrogen peroxide were used. The efficiency of the decolorization was evaluated by measuring the absorbance of the dye solutions. The results show that ultrasound treatment was significantly enhanced in the presence of H 2O 2.

Comparison of H 2O 2/UV, H 2O 2/O 3 and H 2O 2/Fe 2+ processes for the decolorisation of vinylsulphone reactive dyes

Six vinylsulphone reactive dyes were decolorised using three oxidation processes (H 2O 2/UV, H 2O 2/O 3 and H 2O 2/Fe 2+). The efficiency of decolorisation was measured by decolorisation time, absorbance, COD and TOC and the three methods of decolorisation are compared.

Role of skin prick test and serological measurement of specific IgE in the diagnosis of occupational asthma resulting from exposure to vinyl sulphone reactive dyes

OBJECTIVESSome patients with occupational asthma resulting from exposure to reactive dyes have skin reactivity to the causative dyes and specific IgE to reactive dyes have been found in these patients....

Use of ultrasonic energy in reactive dyeing of cellulosic fabrics

The use of ultrasonic energy in dyeing cotton fabrics with monochlorotriazine and vinylsulphone reactive dyes has been studied spectrophotometrically. The dyeings carried out conventionally and by the use of ultrasonic techniques were compared in terms of percentage exhaustion, total amount of dye transferred to the washing bath after dyeing, fastness properties and colour values of the dyed materials. Overall results have shown that the use of ultrasound in reactive dyeing of cellulosic fabrics can result in energy savings, less water consumption, increased depth of colour and better process conditions.

The dyeing of cellulosic fabrics by simultaneous application of azoic components and vinylsulphone or monochlorotriazine reactive dyes

The paper reports preliminary work on the dyeing of cellulosic fabrics by applying vinylsulphone or monochlorotriazine reactive dyes simultaneously with an azoic coupling component.

Interaction of vinylsulphone reactive dyes with cellulosic fabrics. Part 2‐dye associations and dyesurfactant interactions

The ability of reactive dye molecules (CI Reactive Red 180 and CI Reactive Yellow 23) to undergo self‐association and to associate with different surfactants has been examined spectrophotometrically. The stability constants KDS of the dye‐surfactant complexes were calculated at dye:surfactant ratios varying from 1:0 to 1:10 and for different surfactant types (anionic, zwitterionic, nonionic and cationic). Dye uptake on viscose fibre observed for a dye:surfactant molar ratio of 1:0.5 was found to be related to KDS values.

Interaction of vinylsulphone reactive dyes with cellulosic fabrics. Part 1 — dyeing mechanism, fibre characterisation and effects of alkaline electrolytes

Two vinylsulphone dyes were studied by an HPLC technique under alkaline conditions in order to evaluate their various chemical forms. Fabrics made from viscose fibres were dyed under controlled conditions, varying the nature and the quantity of electrolyte used. It was found that sodium chloride is the most efficient salt for a short dyeing times (20 min) while lithium chloride yields higher dye uptake over more prolonged dyeing processes (60 min). The effect of the electrolytes on dye uptake was found to be related to the radius of the solvated cation.