Pretreatment Of Cotton Fabric Research Articles

The influence of triangular silver nanoplates on antimicrobial activity and color of cotton fabrics pretreated with chitosan

The effect of cotton fabric pretreatment with biopolymer chitosan (CHT) on deposition of colloidal triangular silver nanoplates was studied. Also, the influence of deposited silver nanoparticles on color and antimicrobial activity of cotton fabrics was evaluated. Characterization of colloidal silver nanoparticles as well as silver nanoparticles deposited on cotton fabrics was performed using electron microscopy (TEM and FESEM), XRD analysis, atomic absorption spectroscopy, UV–Vis absorption, and reflectance spectroscopy. The cotton fabric turned from white to blue color upon deposition of triangular silver nanoplates. Antimicrobial activity of CHT pretreated cotton fabric impregnated with silver nanoparticles was tested against Gram-negative bacteria Escherichia coli, Gram-positive bacteria Staphylococcus aureus, and fungi Candida albicans. Deposited silver nanoparticles imparted excellent antimicrobial properties to cotton fabric. The standard sterilization procedure of cotton fabric for antimicrobial activity testing resulted in color change of the fabric from blue to yellow. This color change is most likely consequence of transformation of triangular silver nanoplates into nanodiscs and/or their agglomeration into spheroids.

Application of Gamma Irradiated Textile Wastewater for the Pretreatment of Cotton Fabric

The paper presents a method for reducing the amount of freshwater used in the textile industry, by using gamma irradiated textile wastewater for scouring and bleaching in the pretreatment process of knitted cotton fabric. The wastewater samples were irradiated by gamma radiation doses between 3-12 kGy that resulted in a reduced pH value of 9 to nearly neutral 7-7.5, and color reduction percentage of 57- 90%. Thus, the water becomes appropriate for replacing freshwater in the scouring-bleaching stage of cotton fabric. The performance of the cotton fabric samples were also evaluated after scouring & bleaching with irradiated wastewater and found similar to those samples processed with freshwater in respect of whiteness, absorbency and weight loss.

The effect of dendrimer on cotton dyeability with direct dyes

Pretreatment of cotton fabric with poly(propylene imine) dendrimer enhanced its colour strength using C.I. Direct Red 81 and C.I. Direct Blue 78. Application of this dendrimer and the direct dye simultaneously on cotton fabric by the exhaust and the continuous dyeing method were studied; slight improvements in the dyeing results were obtained. Pretreatment of the cotton fabric with dendrimer in an emulsion form using the pad-dry method followed by continuous dyeing markedly increased the colour strength. In addition, level dyeing was obtained, and no negative effects on the fastness properties of the dyes used were observed.

New prospects in pretreatment of cotton fabrics using microwave heating

As microwaves are known to give fast and rapid volume heating, the present study is undertaken to investigate the use of microwave heating for pretreatment cotton fabrics to reduce the pretreatment time, chemicals and water. The onset of the microwave heating technique on the physicochemical and performance properties of desized, scoured and bleached cotton fabric is elucidated and compared with those obtained on using conventional thermal heating. Combined one-step process for desizing, scouring and bleaching of cotton fabric under microwave heating was also investigated. The dual effect of adding urea, (as microwave absorber and hydrogen peroxide activator) has been exploiting to accelerate the pretreatment reaction of cotton fabric. DSC, FT-IR and SEM have been used to investigate the onset of microwave on the morphological and chemical change of cotton cellulose after pretreatment and bleaching under microwave heating. Results obtained show that, a complete fabric preparation was obtained in just 5min on using microwave in pretreatments process and the fabric properties were comparable to those obtained in traditional pretreatment process which requires 2.5–3h for completion.

Chemical analysis of plasma-assisted antimicrobial treatment on cotton

This paper explores the use of plasma treatment as a pretreatment process to assist the application of antimicrobial process on cotton fabric with good functional effect. In this paper, antimicrobial finishing agent, Microfresh Liquid Formulation 9200-200 (MF), and a binder (polyurethane dispersion, Microban Liquid Formulation R10800-0, MB) will be used for treating the cotton fabric for improving the antimicrobial property and pre-treatment of cotton fabric by plasma under atmospheric pressure will be employed to improve loading of chemical agents. The chemical analysis of the treated cotton fabric will be conducted by Fourier transform Infrared Spectroscopy.

A plasma aided process for grey cotton fabric pretreatment

Abstract An effective and cleaner production process was developed in the present work for grey cotton fabric pretreatment with an aid of low-pressure nitrogen plasma in combination with a subsequent wild and one-step wet chemical treatment. The influences of plasma parameters, such as nitrogen pressure, discharge power and exposure time on pretreatment efficiencies and fabric main properties were investigated, as well as a comparison of different processes for the grey fabric. The results show that significant improvements in desizing, scouring and bleaching effects could be available with the aid of plasma previous treatment. The weight loss, impurity removal, capillary rise height and whiteness of the substrate were improved with plasma discharge power from 50.0 W to 300.0 W, and a notable deterioration of fabric strength was also observed at discharge power as high as 350.0 W. Moreover, most of the pretreatment efficiencies were also enhanced for a favorable exposure time from 3.0 min to 5.0 min or 7.0 min, except for the fabric whiteness and a worse deterioration of fabric strength, especially for an exposure time longer than 7.0 min. However, decreased tendencies in most of the pretreatment efficiencies were observed with nitrogen plasma pressures from 20.0 Pa to 100.0 Pa, with a less deterioration of the tensile strength and a less dependence of the fabric whiteness. Furthermore, the nitrogen plasma treatment effect was further proved by a scanning electronic microscopy (SEM) investigation. The recommended pretreatment process with an aid of plasma was 40.0 Pa of nitrogen gas and 300.0 W glow discharge power for 5.0–7.0 min followed with a wild one-step chemical treatment. In comparison with conventional one-step pretreatment process, comparable pretreatment efficiencies and main properties of cotton fabric were achieved by the proposed method with more environmentally friendly by shortening the conventional wet-chemical treatment process and less consumption of chemicals, water and energy.

Pretreatment of cotton fabrics with polyamino carboxylic acids for salt‐free dyeing of cotton with reactive dyes

In this study, polyamino carboxylic acids have been used to improve the dyeability of cotton in a salt‐free reactive dyeing process. These polyamino carboxylic acids were prepared by partial carboxylation of polyvinylamine. Cotton fabric was pretreated with polyamino carboxylic acids and dyed with reactive dyes. The colour strengths of the dyed fabrics were evaluated by measuring the K/S values. The fastness properties (washing, rubbing and light fastness) of the dyed cotton fabrics were also measured. The pretreatment of cotton with polyamino carboxylic acids creates positive charges on the fabric surface. In this way, salt‐free reactive dyeing of cotton or dyeing with only a small amount of electrolyte is possible.

Complete enzymatic pre-treatment of cotton fabric with incorporated bleach activator

The feasibility of a complete enzymatic one-bath pre-treatment of the cotton fabric at low temperature was investigated in this study. The cotton fabric was enzymatically desized, scoured and bleached with an enzyme mixture of starch-degrading enzymes, pectinases and glucose oxidases, respectively. Starch-degrading enzymes hydrolyzed the sizing agent into glucose. Glucose oxidases catalyzed the oxidation of β-D-glucose to D-glucono-ω-lactone and simultaneously generated hydrogen peroxide. The desizing and hydrogen peroxide generation each took one hour. For bleaching, hydrogen peroxide was converted into peracetic acid by incorporating the bleach activator tetra acetyl ethylene diamine (TAED). Bleaching took place at 50°C and neutral pH, where peracetic acid is most effective. Pectinases were added into the pre-treatment bath to remove pectins from fibers and improve their wettability. Whiteness values, water absorbency, polymerization degree and tenacity at maximum load were measured on pre-treated samples. The total organic carbon, pH and biodegradability were measured on residual pre-treatment baths. It was established that hydrogen peroxide can be efficiently enzymatically produced from the sizing agent and converted with TAED to form peracetic acid to bleach the cotton fabric. Cotton fabrics with a medium degree of whiteness, W = 51, and good water absorbency can be obtained at low water and energy consumption.

Effects of the Cotton Fabric Pretreatment on Application Properties of Digital Inkjet Printing with Reactive Dyes

Cotton fabric was directly inkjet printed with reactive dye ink, the ink would appear on the permeability of the fabric, the depth of color yield is low, light fastness is poor. Pretreatment agents with different mass fractions had been used to do the pretreatment of the cotton fabric before ink-jet printing, the results showed that: when the concentration of alginate ester or seaweed was between 1.0% -1.5%, the fabrics had the high color yield and the fixation color rate of the dye was the highest. When the amount of NaHCO3 was 3%, the inkjet printing effect of cotton fabrics was the best; color fastness of colors was all good. After Inkjet printing, the best effect can be achieved by steaming the cotton fabrics under the 100 °Csaturated water vapor for 25min: the colors of black, red and yellow of the K / S value were of the maximum, color fastness was fine.

A Study of Quality Factors for Cotton Fabrics in Ink-Jet Printing

This research focuses on the effects of paste pre-treatment, concentration of sodium alginate, steaming conditions for colour yield and outline sharpness of ink-jet printing. The results show that (a) coating is a better method than padding for paste pre-treatment of cotton fabrics; (b) 102°C × 12min is the best condition for steaming; (c) pattern sharpness is better when the concentration of sodium alginate increases; and (d) color yield diminishes when the concentration exceeds 20g/L. In other words, when the optimum concentration of sodium alginate is 20g/L, the amount of ejected ink can reach as much as 260%. In this study, four reactive dyes (i.e. cyan, magenta, yellow and black) of different chemical constitutions were used, and the colour fastness results against washing and light reveal an acceptable rating above grade 4.

New Techniques in Cotton Finishing

The aim of this study is to investigate the effects of new advanced processes (ultrasound, ozonation, and ultraviolet) on cotton woven fabric's hydrophility and polymerization degrees, breaking strengths, whiteness, and desizing degrees. For this purpose, all trials were realized with water at 63-65°C by the aid of advanced processes. At the end of the experiments, it was noticed that advanced processes can be used in pretreatment of cotton fabrics. Ultrasonic treatment followed by ozonation gives sufficient whiteness degrees and hydrophilily values to the fabric. At the same time, treatment of cotton fabrics with new processes provides savings of thermal energy, water, and chemicals. Moreover, these processes are considered as green processes because they are ecological in certain conditions when compared with conventional processes.

Utilization of acrylates emulsion terpolymer with chitosan as a finishing agent for cotton fabrics

Cotton fabrics were treated with finishing bath formulation containing emulsion lattices based on acrylate monomers, chitosan and polyethylene glycol (PEG) to provide cotton fabrics with antibacterial, UV-protection as well as improvement of dyeing properties with direct, acid and reactive dyes. The terpolymer emulsion, chitosan and PEG concentrations as well as fabric pretreatment with alkali significantly affected the performance properties, antimicrobial activity, UV-protection and dyeing behavior of treated cotton fabric. The finished fabrics were characterized in terms of FTIR, X-ray diffraction, scanning electron microscope (SEM) as well as mechanical properties such as tensile strength, elongation at break (%), abrasion resistance and air permeability. The obtained data showed that the tested fabrics have appropriate antibacterial activity with highly UV-protection properties with increasing chitosan concentration up to 3%. The mechanical properties expressed as tensile strength and abrasion resistance increased after finishing treatment. Moreover, the performance of the finished fabrics and dyeing properties with different dyes classes were greatly influenced by the action of alkali pretreatment of cotton fabrics, adding the polyethylene glycol to the finishing bath formulation as well as emulsion and chitosan concentrations.

Effects of cationic fixing agents on the direct dyeing properties of cotton fabrics

One mono-reactive and two bis-reactive 2,3-epoxypropyl derivatives of quaternary ammonium chloride have been synthesised and characterised using different spectroscopic techniques. The effects of these compounds as fixing agents have been evaluated on the direct dyeing properties of cotton fabrics. The results indicated that pretreatment of cotton fabrics with these cationic agents enhanced the colour strength and fastness properties of direct dyeings over the untreated dyeings without using high electrolyte concentrations. However, bis-reactive derivatives have proved to be more effective than the mono-reactive derivative. Amongst bis-reactive derivatives, the compound with lower steric hindrance has shown superior results.

Effect of Pretreatment with Low Molecular Weight Chitosan on the Dyeability of Cotton Fabrics

The aim of this research is to investigate the influence of low molecular weight chitosan (LWCS) on the dyeability of cotton fabrics. Various concentrations of hydrogen peroxide were used to degrade chitosan to LWCS, which was used to pretreat cotton fabrics under different conditions in order to determine its influence on subsequent acid dyeing of the fabrics. The results showed that the molecular weight of LWCS decreased with increasing concentration of hydrogen peroxide. Additionally, LWCS pretreatment of cotton fabric is beneficial for acid dyeing. The K/S values for fabric dyeing increased with a decrease in LWCS molecular weight and the concomitant increase in concentration; a concentration of 4% LWCS yielded the best result. The anti-bacterial properties of fabrics pretreated with LWCS were better than those pretreated with chitosan. The dye and anti-bacterial fastness after 20 washes were best for fabrics pretreated with LWCS.

Integrated Enzymatic Pre-Treatment of Cotton Fabrics

SUMMARY In our study, the possibility of substitution of alkali scouring of cotton fabrics by enzymatic treatment was analyzed. The applied enzymes mixture, produced by Aspergillus niger IBT-90, contained xylanases and cellulolytic enzymes apart from pectinolytic enzymes. The HPLC analysis of hydrolizate obtained by enzymatic treatment of cotton fabric revealed a significant increase in concentration of pentoses, hexoses and galacturonic acid. It means that the above mentioned enzymes had an integrated activity on cotton fabric. Sorption values (H2O, H2O2) for cotton fabric after integrated enzymatic treatment are higher compared to the ones after alkali scouring.

Development of a one‐stage process for pretreatment and cationisation of cotton fabric

A one‐stage process for cationisation and pretreatment of cotton fabric was developed. Cationisation of cotton cellulose was carried out with 3‐chloro‐2‐hydroxypropyltrimethylammonium chloride, whereas pretreatment comprised enzymatic and oxidative desizing, scouring, bleaching with hydrogen peroxide, combined desizing and scouring as well as combined desizing, scouring and bleaching. Each of these pretreatment operations or their combination with and without cationisation was carried out using three techniques, namely, cold pad–batch, pad–steam and exhaustion. It was found that the cationisation chemicals were compatible with the scouring ingredients and, to a lesser extent, with the formulation of enzymatic desizing. On the other hand, cationisation chemicals were not compatible with oxidative desizing or peroxide bleaching ingredients. Efficiency of the one‐step process for scouring and cationisation was maximised through detailed investigation of the process parameters. The treated fabric can be dyed without electrolyte and the fabrics show a high levelness of colour shade, residual wax content and nitrogen content.

Discovery of Pectin-degrading Enzymes and Directed Evolution of a Novel Pectate Lyase for Processing Cotton Fabric

There is a growing need in the textile industry for more economical and environmentally responsible approaches to improve the scouring process as part of the pretreatment of cotton fabric. Enzymatic methods using pectin-degrading enzymes are potentially valuable candidates in this effort because they could reduce the amount of toxic alkaline chemicals currently used. Using high throughput screening of complex environmental DNA libraries more than 40 novel microbial pectate lyases were discovered, and their enzymatic properties were characterized. Several candidate enzymes were found that possessed pH optima and specific activities on pectic material in cotton fibers compatible with their use in the scouring process. However, none exhibited the desired temperature characteristics. Therefore, a candidate enzyme was selected for evolution. Using Gene Site Saturation Mutagenesistrade mark technology, 36 single site mutants exhibiting improved thermotolerance were produced. A combinatorial library derived from the 12 best performing single site mutants was then generated by using Gene Reassemblytrade mark technology. Nineteen variants with further improved thermotolerance were produced. These variants were tested for both improved thermotolerance and performance in the bioscouring application. The best performing variant (CO14) contained eight mutations and had a melting temperature 16 degrees C higher than the wild type enzyme while retaining the same specific activity at 50 degrees C. Optimal temperature of the evolved enzyme was 70 degrees C, which is 20 degrees C higher than the wild type. Scouring results obtained with the evolved enzyme were significantly better than the results obtained with chemical scouring, making it possible to replace the conventional and environmentally harmful chemical scouring process.

Cationic pretreatment of cotton fabric for anionic dye and pigment printing with better fastness properties

Improved printability with pigment and anionic dyes was obtained after simple cationisation of cotton fabrics with Solfix E. Different print paste formulations were used for printing cationised cotton fabrics with pigment, acid and direct dyes. Print pastes containing a synthetic thickener or a pigment emulsion showed good suitability for printing with pigment and pastes containing Meypro‐gum as a thickener showed good printability with anionic dyes. The prints obtained on cationised cotton showed better overall fastness properties than prints obtained on untreated cotton. After repeated washings, the prints on cationised cotton showed a much smaller percentage colour loss than the prints on untreated cotton fabric.

Enzymatic Recycling of Starch-Containing Desizing Liquors

Starch-containing desizing liquors from the pretreatment of cotton fabrics can be transformed into bleaching liquors by a two-stage enzymatic treatment. The bleaching ability of these liquors is comparable to that of conventional bleaching liquors. The process results in saving of ecologically harmful chemicals and process water. In enzymatic textile processes a loss of enzyme activity occurs, due to the presence of ionic surfactants. This loss of activity can be counteracted by addition of cyclodextrins. Trials have been done to immobilize glucose oxidase on the cheap carrier material cotton, so it can be used more often than only one time as regenerable enzyme.