Woven Wool Fabrics Research Articles

Investigation of herbal dyes from Symplocos racemosa (Lodh) leaves and optimization of procedure for dyeing using synthetic mordants

The present study deals with the soaked and woven wool fabrics that were dyed with natural dyes extracted from the leaves of Symplocos racemosa (Lodh). The optimization was carried out with different conditions like concentration of dye material, time for extraction of dye, dyeing time and concentration of mordants. Out of the three methods of mordanting, the best shades for lodh leaf dye were obtained using post-mordanting with ferrous sulphate and stannous chloride and simultaneous mordanting with copper sulphate and potassium dichromate. Poor results were observed in the case of pre-mordanting. The colour fastness analysis indicated the light-coloured samples were affected more rapidly as compared to the dark ones. In this study, the lodh leaf dyed samples exhibited fairly good to excellent fastness to light in the case of ferrous sulphate and stannous chloride while good to good in both copper sulphate and potassium dichromate respectively and the results of washing fastness analysis revealed that lodh leaf dyed samples had good to excellent fastness to washing.

Extraction of the Microstructure of Wool Fabrics Based on Structure Tensor.

The trends of "fashionalization", "personalization" and "customization" of wool fabrics have prompted the textile industry to change the original processing design based on the experience of engineers and trial production. In order to adapt to the promotion of intelligent production, the microstructure of wool fabrics is introduced into the finishing process. This article presents an automated method to extract the microstructure from the micro-CT data of woven wool fabrics. Firstly, image processing was performed on the 3D micro-CT images of the fabric. The raw grayscale data were converted into eigenvectors of the structure tensor to segment the individual yarns. These data were then used to calculate the three parameters of diameter, spacing and the path of the center points of the yarn for the microstructure. The experimental results showed that the proposed method was quite accurate and robust on woven single-ply tweed fabrics.

Stochastic Modelling of Pilling Degree Changes During the Pilling Process of Wool Fabrics

As a fabric surface defect, pilling gives clothes an unpleasant appearance and is often characterized with small, complex clusters of fibres attaching to the surface of the garment caused by the fibre migration from yarns to the fabric surface as the fabric rubs against itself, another fabric, or even the skin. In this study, a Markov chain model was built based on the pilling propensity of wool fabrics, evaluated with a scale ranging from 1 (severe pilling) to 5 (non-pilling). These grades were defined as the state space of Markov chain. The numerical values of the transition probability matrix related to the pilling degrees were obtained by maximum likelihood estimation (MLE). Based on the matrix, it was intended to model the changes in the pilling process of woven wool fabrics. Furthermore, given that the fabric will eventually be in state 1, 2 or 3, accepted as unpleasant appearance; the conditional mean first passage times for any transient state to enter any recurrent state for the first time were determined.

Rare-earth ions as antibacterial agents for woven wool fabric.

Woven fabrics were bestowed with antibacterial property by the simple adsorption of rare-earth metal ions, and the underlying mechanism was investigated using electron spin resonance (ESR) spectroscopy. The adsorption of Ce3+ ions on wool, silk, and cotton fabrics resulted in significant inhibition of Staphylococcus aureus (a gram-positive bacterium), with maximum antibacterial activities (viable bacterial count compared to the reference) of 4.7, 5.8, and 5.2, respectively. Even after 50 wash cycles, the values remained at 3.9, 2.9, and 4.8, respectively. The adsorption of La3+ and Gd3+ ions on wool fabrics also resulted in antibacterial activities of 5.8 and 5.9, respectively. In addition, wool adsorbed with Ce3+ exhibits a satisfactory antibacterial activity of 6.2 against Escherichia coli (a gram-negative bacterium). Such bacterial inhibition is attributed to Fenton reactions between the adsorbed rare-earth ions and hydrogen peroxide (H2O2) produced during bacterial metabolism, as determined from the ESR spectra collected using the spin trap method in the presence of H2O2. The safety of cerium nitrate was also investigated, and no significant issues arose, indicating that it was a safe antibacterial agent. This facile method of imparting antibacterial properties to natural fabrics may be useful for preventing infections in humans.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11696-021-01999-9.

Selective recovery of palladium by wool resin and woven wool fabric resinrbents

Protein fibers, including wool fibers, selectively adsorb precious-metal ions; hence, they can potentially be used in wastewater treatment applications. Herein, we examined metal-ion adsorption by woven wool fabric and wool resins, especially the adsorption of Pd(II). When woven wool fabrics are treated with chlorine, the cuticle layer is removed from the fiber surface; this treated fabric showed superior Pd(II)-adsorption performance compared with untreated fabric, with a Pd recovery of 81% from an aqueous solution containing 500 mg L−1 Pd(II) for 24 h at 25 °C, which is superior to that of lignin-based adsorbents. The chlorine-treated woven wool fabric and wool resin prepared from this fabric preferentially adsorb Pd when placed in simulated industrial wastewater, even if it contains a variety of other metal ions (e.g., Pd(II), Ni(II), and Cu(II)). Therefore, wool fabrics and resins produced from wool waste can be used as selective adsorbents for the recovery of precious metals such as Pd.

Comparison of Wool Fabric Dyeing with Natural and Synthetic Dyes in View of Ecology and Treatability

The aim of this study was to compare the fastness properties and wastewater quality in obtaining the same color on 100% woven wool fabric with natural (madder) and synthetic (1:1 metal complex) dyes. The same color, with similar wet fastness properties, was obtained on the wool fabric when dyed with either dye. On the other hand, conductivity, chemical oxygen demand (COD), and the ammonia nitrogen (NH3-N) content of dyeings carried out with the synthetic dye mixture were considerably higher than dyeing with madder root extract, and its pH was more acidic. However, the amount of volatile suspended solids and color obtained in natural dyeing was higher than the amount in the synthetic dyeing wastewater.

Physical properties of nonwoven and woven felted fabrics

PurposeThe use of nonwoven fabrics in garment has been, up to now, purely functional and hidden from view. In fact, their uses have been limited to garment interlining in the apparel industry. Felted structures from wool have been limited to the craft market for the production of art and craft objects of decoration. This paper aims to compare the mechanical and thermo-physical comfort properties of a woven wool, a felted wool fabric, a felted wool/polyester and two non-woven synthetic fabrics for apparel use.Design/methodology/approachFabric samples were sourced locally. Five fabric samples were selected: one woolen woven, one felted woven, one polyester/wool non-woven and two non-woven synthetic fabrics. The wool fabric was felted by mechanical action using the Wascator FOM 71P machine. All fabric samples were conditioned before they were tested for their mechanical and thermal comfort properties as per standard test methods.FindingsThe comparative study of the mechanical and thermal properties of the five fabric samples have been successfully investigated as textile materials for commercial garments. In terms of fabric stiffness, drape and handle, the two non-woven synthetic fabrics were, in general, poorer than the woven wool and the felted woven wool fabrics. The synthetic non-woven fabrics also performed poorly in terms of serviceability. But it was found that the nonwoven synthetic fabrics were best suited when thermal insulation is required and were found to be better than the woven felted wool fabric of comparative weight per unit area.Originality/valueThe value of this study is that it demonstrates the scope of felted woolen structures and other synthetic nonwovens fabrics as usable materials, in part or in full, in the development of apparel for winter wear especially in cold environments and where aesthetic appeal is secondary.

Increased bending rigidity of wool fabric imparted by hybrid organic-inorganic sol–gel coatings

Hybrid organic–inorganic coatings prepared by the sol–gel method can impart desirable properties to textiles, but may adversely affect properties such as bending rigidity. This study investigated the causes of increased bending rigidity. Woven wool fabric was pad coated with formulations of methyltriethoxysilane (MTES) and Hercosett polyamide resin, examined by scanning electron microscopy, and the bending rigidities were determined. MTES coatings of up to 3.0% solids on mass of wool did not impart unacceptable bending rigidity. The coatings were not uniform on the fiber surfaces, and the increases in fabric bending rigidity could be partially attributed to inter-fiber bonding. In addition, the coatings “pinned” the edges of the cuticle scales, making individual fibers harder to bend. These effects are only weakly dependent on the Young's moduli of the coating materials.

Surface roughness properties of wool woven fabrics after abrasion

Effects of abrasion on surface roughness properties together with appearance of woven wool fabrics have been investigated. The effects of weft yarn count, weft yarn density, and weave pattern on fabric surface roughness after abrasion were researched. Surface roughness values of control fabric (not abraded) and abraded fabrics after four different abrasion cycles were discussed according to different fabric constructional parameters. It was observed that the greatest decreases in surface roughness values after abrasion were observed in loose fabric structures which had the highest initial fabric surface roughness values (coarse yarn, low yarn density, and low yarn intersection). The results showed that change of roughness properties of wool fabric surfaces after abrasion depends on the initial surface roughness values and on the amount of contact area of fabrics based on the fabric constructional parameters.

A novel approach in single stage combined bleaching and protease enzyme treatments on wool fabrics

Today’s scenario of textile wool industry has been radically changed to use ecofriendly chemicals and enzymes in preparatory and finishing processes due to pollution in the process of chemical treatments. In this research work, a single stage combined bleaching and biopolishing treatment technique for wool fabric was carried out by using acid and alkaline protease enzymes to analyse degradation of wool fabrics. The wool fabrics used were woven wool fabric which undergoes different treatment techniques like bleaching and acid protease, bleaching and alkaline protease, only bleaching treatment, only acid protease and only alkaline protease. The treated wool fabric samples at various process conditions were tested for their low stress mechanical properties such as tensile, shear, bending, compression, and surface. These test results were analyzed and their significant differences in terms of multivariant ANOVA analysis using Design Expert software 8.0 were reported. This novel technique has the ideal effect on wool textile in terms of better softness, weight loss, bending, shear, compression, and tensile strength. Because of mild reaction conditions of alkaline protease enzyme with hydrogen peroxide combined preparatory technique for wool textile treatment would be a promising and prospective method in bioprocessing of wool fabrics.

Fabric hand of a dry finished wool fabric

The appearance and hand of end-use fabrics has become more and more important when purchasing textile fabrics. The finishing parameters have complex influences on the large number of changes that occur in fabric properties during finishing processes. This study focused on the influences of different finishing parameters on mechanical and surface properties in order to discover the most appropriate finishing process according to the requirements of fabric handle and appearance. The KES-F system was used to evaluate fabric hand objectively, as well as the mechanical and surface properties of a woven wool fabric. Four finishing processes were selected, which differed in relation to the temperature when drying (T1=160 C, T2=180 C) and processing conditions during autoclave decatizing (T1=95 C, p1=0.4 bar, T2=110 C, p2=1 bar). The effect of the influential parameters inside four different finishing processes on the mechanical properties and hand of a selected woven fabric was evaluated using the analysis of variance. The results show that tensile properties are much more influenced by the belt pressing process while bending and shear properties are influenced by continuous decatizing process, which is the process that mostly improves fabric stability at the beginning of the dry finishing cycle. When the primary and total hand values were observed, it could be seen that applying chemicals during belt pressing had some consequences, the impacts of which could be observed directly in the resulting hand values.

Study on wettability improvement and its uniformity of wool fabric treated by atmospheric pressure plasma jet

AbstractThe influence of processing parameters on wettability improvement and its uniformity of wool fabric treated by atmospheric pressure plasma jet (APPJ) was explored. A woven wool fabric was treated by APPJ under various treatment conditions such as different treatment time, different oxygen flow rate, and different jet‐to‐substrate distance. The water absorption time of wool fabric was measured to determine wettability improvement. The diffusion photo of water droplet on wool fabric surface was taken by digital camera to reflect wettability uniformity. After APPJ treatment, SEM observation showed that the scales on the wool fiber surface directly facing plasma jet pores were destroyed than those on the other fiber surface. XPS analysis showed that the carbon concentration substantially decreased. The concentration of oxygen and nitrogen significantly increased and but the concentration of sulfur and silicon did not obviously changed. With the addition of oxygen gas, more polar groups such as hydroxyl and carboxyl produced on wool fiber surface. The water absorption time of wool fabric greatly reduced indicating wettability improvement. The diffusion of water droplet on wool fabric surface was also larger and more homogenous suggesting uniform plasma treatment. It was concluded that the wettability improvement and its uniformity of the treated wool fabric increased and then decreased with the increasing oxygen flow rate and jet‐to‐substrate distance, and increased with the increasing treatment time. Therefore to achieve reasonable wettability and its uniformity of the wool fabric treated by APPJ, plasma treatment conditions have to be carefully chosen. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Methods of Coating Textiles with Soluble Conducting Polymers

Soluble conducting alkyl polypyrrole polymers have been applied by either chemical polymerization of the 3-alkyl monomers or direct application of polymer emulsion to the surface. Solution, vapor and spray polymerization methods of coating poly(3-alkylpyrroles) to the surface of woven wool fabrics are explored. Conductive textile samples have also been prepared by applying emulsions of soluble prepolymerized 3-alkylpyrrole to the fabric surface. Direct applications of a conductive paint to the textile surface eliminate the exposure of the substrate to damaging oxidizing agents which allow the coating of more sensitive and delicate substrates. All textiles produced are tested for abrasion resistance and conductivity. For alkyl polypyrrole coated fabrics, the optimum carbon chain lengths are between n=10 and n=14, which result in optimum values of conductivity and solubility. The darkness of the tone is inversely related to the surface resistivity of the resulting conductive fabric. Therefore, deep black coatings have low resistivity whereas light gray coatings on a white fabric surface have higher surface resistivity. Longer alkyl chains result in higher surface resistivity in fabrics. The conductive coating of poly(3-decanylpyrrole) on the textile surface has a better abrasion resistance compared to that of an unsubstituted polypyrrole coating.

A simultaneous antimicrobial and shrink resistance treatment of wool woven fabrics using the polymeric biocide polyhexamethylene biguanide

Recently, a novel, effective, and commercially viable antimicrobial treatment for wool was reported that used a peroxymonosulfate/sulfite pretreatment and the biocide polyhexamethylene biguanide (PHMB). Given the polymeric nature of PHMB used in this antimicrobial treatment, this study investigated whether the treatment would also lead to shrink resistance of woven wool fabrics. It was shown that up to 5% PHMB (on mass of fabric) could be exhausted onto the pretreated wool at 40 °C. Under scanning electron microscope, PHMB was observed to coat the wool surface with no obvious interfiber bonding. PHMB finishing was durable to laundering, had little effect on the tensile strength of the fabrics and only slightly increased the bending rigidity. The finishing conferred strong antimicrobial activity to the fabrics and at the same time reduced felting shrinkage after laundering to an acceptable level. Thus, a single finishing process achieved two important functionalities for wool fabrics, antimicrobial activity and shrink resistance.

The impact of corona modified fibres’ chemical changes on wool dyeing

The main contribution of the present work was to study the impact of Corona-treated wool fabrics’ induced surface properties on dye-bath exhaustion, in order to optimize different dyeing systems. Firstly, the differing chemical aspects of a woven wool fabric's surface were determined using two dissimilar analytical skills (XPS and polyelectrolyte titration). With the intention to establish the ability of low-temperature plasma treatment to change wool fibre morphology which could have an impact on sorption properties, fabrics were dyed with blue acid and blue metal-complex dyes, and dyeing behaviour were studied by means of on-line VIS spectrophotometry. Finally, dyed samples were colourimetricaly evaluated and colour differences calculated. The results provided evidence that the overall carbon C 1s content was decreased while oxygen and nitrogen atoms were increased when using ionized air for fabric modification. It has also been noted that the amount of positive-charged functional groups in various pH ranges are higher for Corona-treated wool fabric in comparison with the untreated that improves hydrophylicity and dyeing properties.

Simultaneous protease and transglutaminase treatment for shrink resistance of wool

A bioprocess for machine washable wool, combining the advantages of both protease and transglutaminase in a simultaneous enzymatic treatment has been developed. This process reduced the felting tendency of woven wool fabrics by 9% at the expense of only 2% weight and tensile strength loss. In contrast to previously described protease-based processes for shrink resistant wool, the anti-felting properties achieved in the simultaneous enzymatic treatment produced insignificant fibre damage, confirmed also by scanning electron images of the fabrics.

Assessment of Reflectance and Color Differences of Wool Fabrics after Abrasion

This paper focuses on the assessment of color differences and percentage reflectance changes that occurred in dyed wool fabrics after different cycles of abrasion for different constructional parameters of the fabric. Twelve wool fabrics having different constructional parameters were used. The fabrics differed from each other by their weft yarn counts, weft densities, warp densities and the fabric weaves. The warp yarn type and count and the warp yarn twist were the same for all fabrics. The dyeing of the fabric samples were performed by using a commercial 1: 2 metal complex dye (Mix Dye). Four different abrasion levels (2500, 5000, 7500 and 10 000) were used. The percentage reflectance values of the abraded fabrics were measured and color differences between the original (control fabric, dyed but not abraded) and abraded fabrics were calculated. Percentage reflectance values and color difference values are presented in figures for changing fabric constructional properties. The percentage reflectance values and color difference values were higher for the wool fabrics having thicker siro-spun weft yarns and having higher weft and warp densities. The effect of increasing abrasion cycles on percentage reflectance values and on color differences was more visible for plain woven wool fabrics. Photographs of the abraded fabrics are presented to show the surface of the wool fabrics after 10 000 abrasion cycles. It was observed that the yarn breakages occurred on the fabric surface because of the lower tenacity of the wool fibers made the fabric surface smoother as a result of the siro-spun yarn structure. It is concluded that the broken ends of the fibers played an important role in surface reflectance beyond a certain abrasion level which was observed to be 7500 cycles.

Relative Contributions of Elasticity and Viscoelasticity of Fibres and Inter-fibre Friction in Bagging of Woven Wool Fabrics

This paper reports an investigation of the relative contributions of elasticity and viscoelasticity of fibres and inter-fibre friction to fabric-bagging behaviour of woven wool fabrics, by carrying out a series of experiments and applying a mathematical model to simulate fabric-bagging behaviour under the testing conditions. Through a large number of computation experiments, the relaxation time of the fibres, τ and three weighting coefficients (κ3, κ4, κ5) were determined for eight woven wool fabrics made from different fibres. It was found that the frictional weighting coefficient, κ5, and the relaxation time, τ are constant across all the fabrics, with κ5 = 0.1 and τ = 100 seconds. The relative contributions of the elasticity and viscoelasticity of the fibres have a narrow distribution, with average values of κ3 = 0.6 and κ4 = 0.3. These results indicate that the three weighting coefficients and the fibre-relaxation time are relatively stable and insensitive to fabric structural differences. The consistent agreement between experimental results and the mathematical simulation over a range of fabrics shows that the model is quite reliable in simulating fabric-bagging behaviour. Using the identified values of the parameters, we simulated the bagging behaviour of a new set of wool fabrics. Reasonably good agreement between simulation and experimental measurement further confirmed that the three weighting coefficients and fibre-relaxation time are relatively stable and that the identified values can be used to simulate woven-wool-fabric-bagging behaviour with reasonable accuracy.

BOOK REVIEW

Book reviewed in this article:Finishing and wool fabric properties — a guide to the theory and practice of finishing woven wool fabrics, Ed. P R Brady (Australian CSIRO Wool Technology, 1997)

Drape Simulation of Woven Fabric by Using the Finite-element Method

In order to understand better the drape phenomenon of fabrics, a non-linear finite-element code was developed and the three-dimensional drape shapes of a woven fabric were simulated by using the code. The woven fabric was assumed to be an elastic material with orthotropic anisotropy. The fabric was considered as a thin flexible plate under the plane stress condition, and the transverse shear strain was included in the formulation. Since a fabric goes through a large displacement and a large rotation during draping, the drape phenomenon of a fabric is considered as a geometric non-linear phenomenon. The finite-element method was thus formulated based on a total Lagrangian approach. Quadrilateral elements with four nodes were used. In order to avoid the shear-locking phenomenon which is commonly observed in thin-plate analysis, a transverse-shear-strain interpolation method was adopted. The mechanical properties of woven fabrics for drape simulations were measured by using the Kawabata instruments. The drape shapes of a woven wool fabric showed reasonably good agreement with experimental results.