Improvement of the Process of Mechanical Dehydration of Five-Layer Wet Leather Semi-finished Products

To improve the process of mechanical dehydration of semi-finished wet leather products, a multilayer dehydration using felt materials – monshons was experimentally investigated. The process is conducted by vertical feed of semi-finished wet leather products on a base plate between rotating squeezing rollers. The D-optimal method of mathematical planning of the experiment and the Kano design matrix were used for conducting experiments. The multi-layer package consists of five layers of semi-finished wet leather products and two layers of moistureremoving materials between each layer, folded over the base plate. The studies were carried out in laboratory conditions on an experimental bench, taking into account the production parameters of processing. As a result of the study, mathematical dependences of the amount of removed moisture for each of five layers of semifinished wet leather product on the feed speed and the pressure of the squeezing rollers were derived. The analysis of the results showed that, with the existing parameters of mechanical dehydration, it was possible to simultaneously squeeze out moisture from five layers of the semi-finished leather product with a minimum pressure of the squeezing rollers and an average feed speed. The productivity of the technological process was more than five times higher in comparison with the productivity of similar roller machines. In the near future, this research methodology will be used to determine the technological factors affecting the extraction of excess moisture from a package consisting of ten semi-finished wet leather products and moisture-removing materials.

Aesthetic and Philosophical Meanings of Indigenous Asante Kente

Indigenous Ghanaian woven fabrics remain traditional cultural pieces, highlighting the value and heritage of the indigenes in the communities. These fabrics are embedded with historical symbolic connotations that help the people to relate effectively and know their past. Recent studies have identified the tools, materials and new innovations in design by traditional weavers. This study seeks to highlight the aesthetics and philosophical connotations of the indigenous Asante Kente which are highly cherished by the indigenes. As a qualitative research, it adopts the narrative research design to interpret empirical information gathered from master weavers and opinion leaders from two weaving communities (Bonwire and Adanwomase) in the Ashanti Region of Ghana. Information on the indigenous Kente of the Asantes is presented, which draws on the types coupled with their philosophical connotations. The worth of the Asante Kente cloth from both aesthetic and philosophical points of view is also presented in the study. It recommends further studies to promote the artefacts and the Ghanaian culture at large.

Development of Superhydrophobic Cotton Fabric Using Zinc Oxide Nanoflower/Polydimethylsiloxane (PDMS) Nanocomposite Coatings

Nanoflower is anticipated to become a very smart material due to its unique properties such as high surface to volume ratio. A hydrothermal method was used in this study to prepare the zinc oxide (ZnO) nanoflower and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). The average particle size of the ZnO nanoflower was calculated as 21nm according to the Debye-Scherrer formula. The SEM result gives the surface morphological information of the ZnO nanoflower, which confirms the formation of the ZnO nanoflower. The ZnO nanoflower was dispersed in PDMS and coated onto cotton fabric to get the superhydrophobic fabric. The hydrophobicity was determined by measuring the water contact angle by the Sessile drop method and it was observed that coated fabrics have the highest contact angle, 140⁰ at 0.5% ZnO nanoflower concentration. The present study offers a method of fabrication of superhydrophobic cotton textile using ZnO nanoflower/PDMS polymer nanocomposites.

Auxetic Yarn: Fundamentals, Influencing Parameters, Application Areas and Challenges

The mechanical behaviour of auxetic materials and structures is the most distinctive characteristic, which differs from that of conventional engineering materials due to the negative Poisson’s ratio. Auxetic materials have the fascinating feature of widening when stretched and contracting when compressed. In recent times, the research of auxetic materials based on textile structures has received a lot of interest. Auxetic effect development at the yarn phase is a new and exciting field of study. Many researchers already developed different types of auxetic yarns, such as the helical auxetic yarn, the plied auxetic yarn, the semi-auxetic yarn etc. The helical auxetic yarn (HAY) is the most commonly mentioned auxetic yarn. It is made up of a rigid wrap and an elastic core yarn. However, it is interesting that auxetic yarns can be produced from conventional non-auxetic fibres through the conventional spinning system as well. The helical auxetic yarn is a new type of yarn with a wide variety of possible applications. Moreover, pore-opening characteristics of auxetic yarns make it a potential candidate in the fields of technical textiles, such as medical textiles, filter application, protective textiles etc. Fabrication of auxetic textiles by utilizing auxetic yarns through simple weaving and knitting technology opens the door to new applications. The aim of this paper is to address the fundamentals of auxetic yarns, such as structure, shortcomings, production techniques, as well as the influencing process parameters. From various research works, it is evident that the wrap helical angle, the core/wrap diameter ratio, and the initial moduli of wrap component are the most vital processing parameters during the production of auxetic yarns. Finally, some potential application areas and challenges of auxetic yarns are also addressed briefly in this paper.

Review on Extraction and Application of Natural Dyes

With the improvement of living standards, everybody is very much conscious about the environmental protection and health safety. Natural dyes have attracted more attention to the industry due to exhibiting better biodegradability and more compatibility with the environment. Characteristic colours that are gathered from common assets can be categorized as either plant, creature, mineral, or microbial colours and can be used for colouring a wide range of regular filaments. Late examination shows that it can likewise be utilized to colour a portion of the manufactured filaments too. Normal colours are not just utilized in the shading of material filaments, they are also utilized for food, prescriptions, handiwork articles, and leather preparing. Extraction and purification play a vital role in the processing of natural dyes. There are different types of extraction process currently available for these natural dyes, such as solvent extraction, aqueous extraction, enzymatic extraction and fermentation, extraction with microwave or ultrasonic energy, supercritical fluid extraction, and alkaline or acid extraction. All these extraction processes have their own advantages as well as some drawbacks depending on the parameters that need to be maintained during the extraction process. Appropriate extraction can be beneficial for specific types of such dyes. In this paper, the classification, characteristics, extraction methods, and the application of natural dyes are introduced in an organized manner.

Textile Finishing Using Polymer Nanocomposites for Radiation Shielding, Flame Retardancy and Mechanical Strength

The uses of nanotechnologies in textiles are strategic and allow textiles to become multifunctional. There is an ever-increasing demand for new functionalities, like flame retardancy, radiation shielding, improved mechanical strength etc., for highly specific applications. There is no industrial supply for the above-mentioned functionalities. Keeping in view of this background, surface treatment becomes one of the most important methods to create new textile properties. Polymer nanocomposites based on coatings for textiles have a huge potential for innovative modifications of surface properties like flame retardancy, radiation shielding and improved mechanical properties, which can be applied with a comparatively low technical effort and at moderate temperatures. This review compiles recent research on polymer nanocomposites for functional finishing of textiles to understand the theoretical and experimental tools on polymer nanocomposites and their applications in textiles.

Biaxial Cyclic Loading of Woven Fabrics

For the purpose of this paper, investigations were carried out on specifically designed fabrics with different structural parameters. The biaxial cyclic loading of fabrics and its consequences were investigated. The weave structures with the smallest weave units (plain weave, basket weave 2/2, rib weave 1/1 (2+2) and rib weave 2/2 (1+1) with the same warp and weft density (24 ends/cm and 24 picks/cm) were selected. Biaxial cyclic loadings of fabrics were performed on a newly developed patented device. The influence of the low level of cyclic loadings of fabrics on the change of tensile properties in warp and weft direction was investigated. The results showed that the low level of biaxial cyclic loading can lead to a permanent linear deformation of fabrics. Despite the fact that the forces that cyclically strain the fabric in two directions amount to 10% of the breaking elongation, after a certain number of cycles there is an irreversible deformation and reduction of breaking forces, but sometimes they can result in an increase in breaking forces. It was found that the tensile elongation of fabrics is affected both by thread crimping and by the structural properties of fabrics resulting from changes in the weave.

Textile Art Creation as a Tool for Raising Awareness of Corruption in Ghana

Textile art possesses the ability to communicate with the viewer in as much as the viewer understands the visual images. It involves art made of textiles or about textiles by utilising techniques such as embroidery, patchwork, quilting, applique, tapestry, dyeing, and painting, among others. This study explores the use of conventional and non-conventional textile materials in a mixed-media technique in the production of artefacts aimed at raising awareness of corruption in Ghana; a national canker that is retarding the country’s growth. It employed a practice-based research approach to gain new ideas or knowledge in the study through practice. The study revealed that the artefacts serve as an effective communication tool to create awareness of the dangers of corruption in the country, thereby expanding the frontiers of textile art by exploiting various techniques and materials.

Sustainability Issues of Various Denim Washing Methods

Denim washing is increasingly joining the list of indispensable processes of meeting the demands of the world’s shifting fashion industry. Other than this, there is a rising trend in the sustainability perception among both producers and customers in the modern world. However, denim washing is considered to have direct impacts on the environment because of its chemical discharge and many other pollutants emitted during the process which affect water supplies. In the process, the denim industry encounters challenges at every level. Therefore, there is need for studying sustainable problems associated with denim washing. The unseen soul of the denim industry is technology, as nothing can be transformed without technological advancement. Sustainability problems of conventional washing have been addressed in this paper (i.e. pp spray washing, bleaching washing, stone washing, sand blasting etc.). Furthermore, the paper describes how sustainability can be achieved through the most recent washing techniques, such as laser, waterjet, nanobubble, ozone, NoStone, potassium permanganate alternatives etc. The introduction of new technologies has triggered a dramatic shift in the denim washing industry in terms of water usage, electricity and chemicals as well as improved quality. Consequently, it is undoubtful that the recent technologies in denim washing are crucial in making the industry sustainable. Moreover, the paper describes the idea of digitally printed denim and the available software for measuring sustainability in the process of denim washing.

Probable Ways of Tannery’s Solid and Liquid Waste Management in Bangladesh ‒ An Overview

The leather industry has been marked as a top-priority sector due to its potential growth and economical contribution in Bangladesh. However, these industries are unable to meet the compliance issue due to the environmental pollution. Leather processing is a complex process based on chemicals and mechanical methods. A substantial amount of solid and liquid wastes is generally produced during the production of leather. As most of the tanneries do not have a central effluent treatment plant and advanced management technologies, they produce 20000 m3 of liquid waste and 232 tonnes of solid waste per day in Bangladesh, which poses a significant risk to the environment and human health unless it gets well treated. In this modern era, it is indispensable to implement new technologies to treat liquid waste properly as well as innovative disposal techniques for solid waste to reduce pollution and health hazards. This study, by using a non-systematic approach based on literature reviews, is designed to summarize the kinds of solid and liquid waste management techniques around the world which should be implemented in the tanneries of Bangladesh to mitigate environmental pollution. We hope that this study can be a great resource and provide a pathway for leather industries in Bangladesh to get familiar with effective treatment technologies of solid and liquid wastes.