Dimensional properties of low temperature plasma and silicone treated wool fabric

Three different silicone polymer systems, such as aminofunctional, epoxyfunctional, and hydrophilic epoxyfunctional silicone polymers, were applied onto plasma pretreated wool fabric to improve the dimensional properties. The results showed that the plasma pretreatment modified the cuticle surface of the wool fiber and increased the reactivity of wool fabric toward silicone polymers. Felting shrinkage of plasma and silicone treated wool fabric was decreased with different level depending on the applied polymer system. Fabric tear strength and hand were adversely affected by plasma treatment, but these properties were favorably restored on polymer application. Therefore, it has been concluded that the combination of plasma and silicone treatments can achieve the improved dimensional stability, and better performance properties of wool fabric. The surface smoothness appearances of treated fabrics were measured using a new evaluation system, which showed good correspondence with the results of KES-FB4 surface tester.     

Surface Modification of Wool Fabric with POSS® Nanomaterial

Wool fabrics, without any surface treatment, can undergo undesirable and irreversible structural changes of wool fiber during washing under heat and mechanical agitation, leading to high shrinkage of wool garments. The traditional method based on polyamide resin can prevent felting and/or shrinkage of wool textiles, but adversely affect the surface hydrophobicity. In the present study, a treatment solution was developed based on TriSilanolIsooctyl POSS® and 3- mercaptopropyl trimethoxysilane, which created wool surface with increased hydrophobicity and highly resistant to shrinkage or felting, as measured after 3×5A wash cycles (equivalent to 24 domestic washes). After the treatment, the wool fabric appeared to be superhydrophobic with a water contact angle of above 150°, compared to the untreated fabric. The treatment has marginal effect on mechanical performance as observed in tensile properties. Scanning electron microscopic images revealed a coating of POSS® on the wool surface. The dyeing of untreated and treated fabrics appeared to be uniform to the naked eye, though spectrophotometric analysis indicated a difference in the extent of dyeing performance. This research showed that POSS®-based treatment is a potentially effective approach for developing shrink-resistant wool textiles with enhanced surface hydrophobicity, in contrast to traditional chlorine/polyamide resin treatment.     

Knitted fabric relaxation by ultrasound and its characterization with yarn-pullout force

An investigation on the dimensional properties of plain knitted fabric produced from cotton yarn and subjected to different relaxation treatments is presented in this paper. The main aim of this research is to characterize the internal energy of fabric by using yarn-pullout test method in ultrasonic relaxation state and compare it with other common mechanical relaxation treatments. A comprehensive experimental analysis showed that, by using ultrasonic waves, the area geometry constant value (k _s) achieved was higher than the conventional relaxation methods. Then, we introduced residual-energy forming and loss-energy uniforming. The former appeared due to fabric shrinkage and the later one appeared due to release of fabric loops from extra forces which imposed during knitting process. The results also indicated that ultrasonic waves energy causes more uniformity on loop and consequently, the fabric reaches to a less internal energy than washing treatment.     

Laser treatment of the wool fabric for felting shrinkage control

Laser treatment is one of the technologies which are able to eliminate all the adverse effects on the environment caused by chemical treatment commonly used in textile finishing. In this research, we investigated the use of laser treatment for the purpose of wool felting shrinkage control, and compared its effectiveness with that of the traditional chlorination treatment method. The wool fabric was exposed to an industrial laser at two different power levels and two sweep speeds. We found that upon selecting the appropriate treatment parameters, the laser treatment is effective in reducing felting shrinkage of wool fiber by its etching effects on the scales of the wool fiber as shown by the scanning electron micrographs. Too high energy exposure of the wool fiber by laser radiation causes excessive fabric strength loss. We also found that the laser-treated wool has felting shrinkage reduction similar to that treated using the traditional chlorination procedure. The laser technology presents an alternative wool processing method to replace the tradition chlorine treatment method. If this technology can be applied to wool felting-proof finishing on a commercial scale, it will significantly benefit the environment by completely elaminating the harzardous chlorine compounds currently by the industry.     

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.     

The combined use of cutinase,keratinase and protease treatments for wool bio-antifelting

A combined treatment method of cutinase, keratinase, and protease was applied in the wool processing to modify the wool properties. The results demonstrated that individual protease treatment did not obviously improve the wettability and anti-felting property of wool fabrics. The combined process of cutinase and protease seemed more efficient than the keratinase-protease method, the obtained wettability and anti-felting ability of wool fabric were more encouraging. The combined use of cutinase, keratinase, and protease treatments endowed wool with more satisfactory properties compared to other methods. The contact angle of the protease-treated wool fabric reduced to 66 ° and the area shrinkage decreased to 5.2 % with an acceptable strength loss of 14 %. Reaction mechanism of the three-step enzymatic process was proposed in this paper. The data from amino acid analysis revealed the cooperative actions of cutinase, keratinase, and protease treatments during the combined enzymatic processing.     

Transglutaminase treatment for improving wool fabric properties

The microbial transglutaminase (mTGase) is used as a bio-catalyst to repair the wool damages caused by chemical or enzymatic treatments. In this paper, the effect of mTGase on the degree of yarn strength, area shrinkage, wettability, and the dyeing properties of wool was investigated. Through mTGase treatment, the yarn strength was improved about 22.2 %. The knitted wool fabrics treated with mTGase after pretreatment of H₂O₂ and protease displayed 7.5 % of area shrinkage and about 22.3 % recovery in tensile strength when compared with those treated without mTGase. Also, mTGase treatment could improve the wettability and dyeing properties of wool fabrics. With the increase of mTGase concentration, the initial dye exhaustion increased significantly and the time to reach the dyeing equilibrium was shortened. It was evident that the improvement of dyeing properties was closely related to the improvement of wettability performance of wool fabric by using transglutaminase.     

Effect of low temperature plasma treatment on wool fabric properties

Low temperature plasma (LTP) treatment was applied to wool fabric with the use of a non-polymerizing gas, namely oxygen. After the LTP treatment, the fabric properties including low-stress mechanical properties, air permeability and thermal properties, were evaluated. The low-stress mechanical properties were evaluated by means of Kawabata Evaluation System Fabric (KES-F) revealing that the tensile, shearing, bending, compression and surface properties were altered after the LTP treatment. The changes in these properties are believed to be related closely to the inter-fiber and inter-yarn frictional force induced by the LTP. The decrease in the air permeability of the LTP-treated wool fabric was found to be probably due to the plasma action effect on increasing in the fabric thickness and a change in fabric surface morphology. The change in the thermal properties of the LTP-treated wool fabric was in good agreement with the above findings and can be attributed to the amount of air trapped between the yarns and fibers. This study suggested that the LTP treatment can influence the final properties of the wool fabric.     

A comparative study on wool bio-antifelting based on different chemical pretreatments

The enzymatic antifelting of wool with proteases, which is referred to as bio-antifelting, has become a promising eco-friendly alternative to conventional chlorination treatment. However, wool bio-antifelting in industrial scale has not been reached so far due to its unsatisfactory shrink-resistance and uncontrolled action in fiber damage. In this paper, the action and mechanism of two kinds of chemical pretreatments, i.e., hydrogen peroxide and dichlorodicyanuric acid pretreatments on the shrink-resistance of protease-treated wool fabrics were investigated and compared. The results show that although hydrogen peroxide treatment could decrease the shrinkage of wool in comparison with untreated one, its contribution to the enhancement of wool bio-antifelting with protease was not remarkable. An effective shrink-resistance can be obtained when the wool fabric was treated with dichlorodicyanuric acid and protease consecutively. Both of the two chemical pretreatments could improve the wettability and whiteness of protease-treated wool. The mechanism of different pretreatments for enhancing wool bio-antifelting with protease was further illustrated and compared via several microscopic analyses such as Allwörden’s reaction, FTIR-ATR and SEM. The comprehensive comparison for wool bio-antifelting based on different chemical pretreatments reveals the difference of hydrogen peroxide and dichlorodicyanuric acid pretreatments in antifelting mechanism, which is valuable for getting a clear understanding and further modification of wool bio-antifelting.     

Application of silver nanoparticles as an antibacterial mordant in wool natural dyeing: Synthesis,antibacterial activity,and color characteristics

Madder is a natural colorant which is commonly applied with metal salts as a mordant to improve its affinity to fibers and color fastness. Madder produces an insoluble complex or lake in the presence of metal ions on mordanted fabric. In this study, wool fabric was pretreated with AgNPs (silver nanoparticles) as a mordant, then dyed with madder. The wool fabric samples were examined by scanning electron microscopy (SEM) and their colorimetric characteristics were evaluated. The formation of spherical silver nanoparticle was confirmed using UV-Visible spectroscopy, SEM images, and elemental analysis. The average size of synthesized silver nanoparticles on the surface of wool fibers is around 73 nm. The dyed wool samples were pretreated with different concentration of Ag⁺ ions or AgNPs, which showed higher color strength value compared to untreated dyed wool fabric. This pretreatment also presented good antibacterial activity.     

Functional modification of wool fabric by thiol-epoxy click chemistry

The paper reports modification and characterization of wool fabrics achieved through thiol-epoxy click chemistry. A pretreatment with tris (2-carboxyethyl) phosphine (TCEP) as an effective reducing agent was carried out to produce thiol groups on wool surface. Glycidyl trimethyl ammonium chloride (GTAC) was later covalently bonded with wool fibers via thiol-epoxy reaction. The reaction was confirmed by SEM, FTIR, Raman and TG analysis. Antibacterial activity, antistatic property, hydrophilicity and dyeability of treated wool fabric were assessed. The results demonstrated that TCEP-GTAC treatment can endow wool fabric good antibacterial and antistatic properties as well as improved hydrophilicity. Tensile strength studies indicated fiber strength loss of ~12 % on modification.     

Effect of wool surface modification on fluorocarbon chain re-orientation

There is an increasing demand for air-dry performance of fluorocarbon finished materials. Thus, surface modifications of wool fabrics were evaluated. Untreated, gaseous fluorinated, Chlorine/Hercosett processed 100 % wool fabrics were treated with different fluorochemicals and their liquid repellency after washing, and dry cleaning were evaluated. The results indicated that Chlorine-Hercosett treated samples, wool with a positive charge, after few washing cycles, showed better air dry performance with higher level of repellent properties. In addition, the comparison of the wool surface modifications treatment with different applied fluorochemicals, with different commercial formulations, illustrated that the fluorocarbon chain re-orientation and fastness properties are more affected by the nature of the wool surface while the used fluorocarbons showed more or less similar behaviours. In general, the fluorination increases fabric stiffness with lower fabric formability. The surface interface was effectively probed by X-ray Photoelectron Spectroscopy, XPS, which enabled the characterisation of the loss of surface lipids, the nature of the fibre oxidation and the deposition of fluoropolymers.     

Application of artificial neural network (ANN) for prediction of fabrics’ extensibility

In the field of clothing technology, prediction of the fabric properties is very important because the fabric is the basic element of every clothing item. Knowing the fabric properties it is possible to predict fabrics’ behaviour during process of clothing manufacturing (in phase of cutting, sewing and ironing) as well as clothing items’ behaviour during usage. According to the fabrics’ characteristics and model design it is possible to predict appearances of the clothing items and their draping which can be presented with many computer simulations. In this paper extensibility of the fabric which appears during a small forces loading on the fabrics are investigated. Loading of small forces on the fabric appears in each phases of clothing manufacturing processes and during usage of clothing items. Investigations are managed on 50 fabrics which are weaving in twill weave and 100 % wool. The basic characteristics of fabric (density of warp and weft, mass per unit area, thickness) are defined according appropriate standard methods and tensile properties in the warp and weft directions are measured using KES-FB1 measuring system. Using an artificial neural network (ANN) prediction of extensibility properties of the fabrics are done, results are compared with experimental values and deviations are determined. ANN is an adaptive system that changes its structure based on external or internal information that flows through the network during the learning phase. They can be used to model complex relationships between inputs and outputs or to find patterns in data. Based on the implemented investigations, minimal deviations between experimental and predicted values are obtained and can be concluded that ANN can be used for prediction of the fabrics properties.     

Development of durable shrink-resist coating of wool with sol-gel polymer processing

Knitted wool fabric was pre-treated with the serine type protease, Esperase 8.0L (EC3.4.21.62), and sodium sulphite followed by an immersion treatment with a sol-gel hybrid polymer. To enhance the durability of the sol-gel treatment on wool, one of two different alkoxysilanes containing coupling epoxy or mercapto groups were added to the sol-gel hybrid. The combination of protease treatment with an immersion sol-gel treatment achieved wool fabric that was lightweight with a soft handle and had combined shrink-resistance and hydrophobic properties without fibre discoloration. The addition of an alkoxysilane with a mercapto coupling group within the sol-gel hybrid gave better performance than using an alkoxysilane with an epoxy coupling group in terms of polymer uptake, fabric shrink resistance, whiteness and durability to washing.     

Effect of pineapple protease on the characteristics of protein fibers

A pineapple protease, bromelain, was used to improve the dyeing properties of protein fibers such as wool and silk. The optimal condition for the activity of the pineapple protease was about 60 °C at pH 7. The wool and silk were treated with the protease extracted from a pineapple and the K/S values of the dyed wool and silk were measured using a spectrophotometer in order to compare the dye uptake. The protease treatment enhanced the dyeing properties of protein fibers without severe changes in mechanical properties. The surface appearances of protease-treated fibers were observed by microscopy.     

Dimensional stabilization of cotton plain weft knitted fabric using mercerization treatment

Investigation on dimensional stability of cotton plain weft knitted fabric manufactured from rotor spun yarn, subjected to mercerization treatment has been represented. Several fabric samples were mercerized considering variation in time of treatment, bath temperature, concentration of alkali solution and also mercerizing tension. Values of constant of course (K _c ), constant of wale (K _w ), the area geometry constant (K _s ) which are indicative of fabric dimensional stability were calculated after treatment for mercerized samples. Then, these values were compared with those of un-treated samples subjected to dry and wet relaxation and also were compared with each other. Based on the effect of each variable itself and their simultaneous effect, it was concluded that, mercerization treatment and considered parameters had a distinctive influence on dimensional stability of the fabric. Mercerized samples had better dimensional stability in comparison with un-treated ones. A comprehensive experimental analysis showed that, there is meaningful difference between K _s values of the samples mercerized at various conditions. Also, the area geometry constant (K _s ) achieved after treatment was higher than that of other relaxation methods.     

Effect of washing cycles on behavior of core spun cotton/spandex interlock structures

Effect of machine washing on structural behavior of core spun cotton/spandex interlock fabrics made with high, medium and low tightness factors has been investigated. Results are compared with those for similar fabrics knitted from 100 % cotton. Structural behavior of cotton/spandex and cotton fabric samples was observed under full relaxation and washing treatments up to 10th cycle. Based on these data, dimensional constants (U-values) were predicted under 95 % significance level. Higher course and wale densities, stitch densities, dimensional constant values, linear and area dimensional shrinkages are reported with cotton/spandex interlocks. After treatment levels, cotton/spandex showed the dimensional constants with lesser CV %. With increasing fabric tightness, decreasing of length shrinkages and area shrinkages and increasing of width shrinkages are reported in cotton/spandex interlock structures. Cotton/spandex interlocks showed longitudinally and highly deformed shapes after treatments. Fabric tightness affects significantly on structural behavior of cotton/ spandex and cotton structures during relaxation.     

Atmospheric plasma advantages for mohair fibers in textile applications

In this study, mohair fibers were treated by air and argon plasma for modifying some properties of fibers. The fibers were evaluated in terms of their hydrophilicity, grease content, fiber to fiber friction, shrinkage, dyeing, and color fastness properties. The surface morphology was characterized by SEM images. The results showed that the atmospheric plasma has an etching effect and increases the functionality of a wool surface, which is evident from SEM and FTIR-ATR analysis. The hydrophilicity, dyeability, fiber friction coefficient, and shrinkage properties of mohair fibers were improved by atmospheric plasma treatment.     

Dyeing and fastness properties of natural dyes extracted from eucalyptus leaves using padding techniques

A natural dye extracted from eucalyptus leaves was applied to a silk and wool fabric by the use of two padding techniques, namely the pad-batch and pad-dry techniques under different conditions. Silk and wool fabrics dyed in a solution composed of eucalyptus extract from leaves showed a shade of pale yellow to brown. The exception was when the fabric was dyed with ferrous mordant, resulting in a shade of dark grayish-brown. The fastness properties ranged from good to excellent, while light fastness was fair to good.     

Effect of repeated laundering and Dry-cleaning on the thermo-physiological comfort properties of aramid fabrics

This research investigated the effect of repeated laundering and dry-cleaning on the physical and thermophysiological comfort properties such as air permeability, water vapour resistance and thermal resistance of fabrics made of meta-aramid (Nomex®) fibre. Two different types of fabric were selected for the study and subjected to repeated laundering and dry-cleaning (1, 5 and 10 cycles), which is commercially used for the care and maintenance of these fabrics. The fabric thickness, areal density, thermal resistance and water vapour resistance values increased with the number of laundering cycles, whereas the air permeability decreased due to the fabric shrinkage and swelling. On the other hand, the thickness and air permeability of the dry-cleaned fabric samples increased with the number of cycles; while the water vapour resistance and thermal resistance decreased. The scanning electron microscopy images showed the structural changes as indicated by the longitudinal fibrillation in the fabrics subjected to laundering or dry-cleaning.