There is an increased awareness of the textile dyeing and finishing sector’s high impact on the environment due to high water consumption, polluted wastewater, and inefficient use of energy. To reduce environmental impacts, researchers propose the use of dyes from natural sources. The purpose of using these is to impart new attributes to textiles without compromising on environmental sustainability. The attributes given to the textile can be color and/or other characteristics. A drawback however, is that the use of bio-sourced dyes is not free from environmental concerns. Thus, it becomes paramount to assess the environmental impacts from using them and improve the environmental profile, but studies on this topic are generally absent.

The research presented in this thesis has included environmental impact assessment, using the life cycle assessment (LCA) tool, in the design process of a multifunctional polyester (PET) fabric using natural anthraquinones. By doing so an eco-design approach has been applied, with the intention to pave the way towards eco-sustainable bio-functionalization of textiles.

The anthraquinones were obtained from the root extracts of the madder plant (Rubia tinctorum L.), referred to as madder dye. The research questions were therefore formulated related to the use of madder dye. Three research questions have been answered: (I) Can madder dye serve as a multifunctional species onto a PET woven fabric? (II) How does the environmental profile of the dyeing process of PET with madder dye look like, and how can it be improved? (III) What are the main challenges in using LCA to assess the environmental impacts of textile dyeing with plant-based dyes?

It is concluded that there is a potential for the madder dye to serve as a multifunctional species onto PET. Based on the encouraging result, a recommendation for future work would be to focus on the durability of the functionalities presented and their improvement potential, both in exhaustion dyeing and pad-dyeing. LCA driven process optimization of the exhaustion dyeing enabled improvement in every impact category studied. However, several challenges have been identified which need to be overcome for the LCA to contribute to the sustainable use of multifunctional plant-based species in textile dyeing. The main challenges are the lack of available data at the research stage and the interdisciplinary nature of the research arena. It is envisaged that if these challenges are addressed, LCA can contribute towards sustainable bio-functionalization of textiles. 

The demand for textile fibres is growing quickly. However, global cotton production has stabilized around 25 Mton/year. This is a sound development since cotton cultivation causes major sustainable development issues. Even if regenerated cellulose fibre production steadily grows, it is still only from a sixth to a fifth of cotton volumes. Hence, it is essential to find resource-efficient routes to generate alternatives to virgin cotton. There are many promising research initiatives that discover the possibility to utilize waste streams of neat cotton and cotton in fibre blends as raw materials for dissolving pulp for regeneration into, for example, viscose or Lyocell. However, there is a much simpler and energy-efficient route at hand. If fabrics are disintegrated mechanically, the separated fibres can be turned into yarn again. However, since fibre length is a key parameter to accomplish strong and durable textiles, fibre length loss upon tearing should be minimized. This study evaluates how fibre length distribution alters upon tearing of post-consumer cotton waste of two different constructions: denim and single jersey; and different degrees of wear, rendering four different fractions: (1) barely worn denim, (2) rather worn denim, (3) barely worn single-jersey and (4) rather worn single-jersey. Before tearing, the garments were dissembled, their yarns were characterized, fibre length distributions were manually determined for (1)–(4). Length analysis of the recovered fibres after tearing revealed that the length drop was most severe for (a) the finer single-jersey and (b) the barely worn fractions. The findings suggest that significant wear does not exclude from mechanical recycling.

Description

Advances in Textile Biotechnology, Second Edition examines the latest in biotechnology for the fiber and textile industry. This new edition has been fully revised to include the current essential areas of development in the field, covering both natural and synthetic fibers. Chapters cover the latest technology in bioprocessing for bast fiber, PVA, polyester, wool and silk before exploring issues of enzyme stability. Essential areas of application and development are then considered, including biomedical textiles, silk materials for biotechnological applications, bacterial cellulose, the ink jetting of enzymes, and the role of enzymes, wool and silk fibers.

Containing groundbreaking research, this book will be essential reading for manufacturers, designers and engineers in the textiles industry, textile and fiber scientists, and academic researchers and postgraduate students working in the area of textile technology.

Key Features

• Provides a thorough overview of current and future focuses of biotechnology in the fiber and textile industry
• Presents fully revised content, with a new focus on biosynthesis and bioprocessing for novel textile fibers, both synthetic and natural
• Enables readers to understand and utilize the benefits of biotechnology for the manufacture and production of textiles

Readership

Textile manufacturers, designers and engineers in the textile industry; textile and fibre scientists; academic researchers and postgraduate students in textile technology; experts in the biology, chemical and environmental engineering industries

Smart textile is a term referring to the textiles that could interact with their environment, receiving input and giving output based on their applications. Among smart textiles, electrically driven smart textiles (E-textiles) are being produced by various methods and materials integrated with textile substances. Graphene is one of these compounds that could be integrated into the polymer or integrated into the textile materials such as fibres. Therefore, other elements could be doped or immobilised on the graphene nanosheets for a wider range of applications, such as catalytic and electrocatalytic systems.  

However, finding the most applicable and efficient method to integrate graphene into the textile fibres and further establishing a method for catalyst immobilisation are challenging and require focused research.  

Therefore, this doctoral thesis focused on the innovative concept of integration of graphene and immobilisation of iron nanoparticles on it. Evidence from the systematic experiments was gathered for the case of dip-coating of polyester textiles with graphene oxide dispersion and enhancing the electrostatic bonding between fibres and graphene oxide nanosheets. In the second step, systematic experiments were gathered for the case of immobilisation of an inorganic catalyst (zerovalent iron) on textile supports. The goal of this thesis is to establish the feasibility of a mild and applicable method for textile material supports, which requires low temperature and mild pH, and further fabrication of heterogeneous catalytic and electrocatalytic systems for wastewater treatment. Polyester was chosen as the textile support material for graphene oxide coating and catalyst immobilisation due to its availability and cost-effectiveness.  

The thesis has four distinct parts related to (a) Pre-surface-charge modification of the polyester for strong electrostatic bonding between polyester and graphene, (b) Design a continuous yarn coating system for mass production of graphene-coated conductive yarns, (c) Immobilisation of Fe0 on graphene-coated polyester textiles and optimising their feasibility in catalytic systems and (d) Design and prove the feasibility of knitting a fully textile-based reactor having two anodic and cathodic sections by using rGO-Fe0 yarns and stainless-steel multifilament yarns, respectively as a concept of electro-Fenton wastewater treatment.  

Diverse analytical and instrumental techniques were used to monitor the surface modification of the polyester textiles and conductivity of the resulting textiles; moreover, the electromechanical and electrothermal properties of the graphene-modified textiles were examined. Further, the efficiency of catalyst immobilisation, physio-chemical properties of the immobilised catalyst, and their catalytical activities in dye removal from the water was studied. Results showed that surface charge modification of polyester fabric with both chitosan and hexadecylpyridinium chloride (HDPC) gives the most homogeneous graphene coating, resulting in high conductivity and very good fastness. Furthermore, results from scanning electron microscope (SEM), Differential scanning calorimetry (DSC), and UV/Visible spectrophotometry prove the success of immobilisation of zerovalent iron on the graphene-modified textiles. 

The novelty of the research presented in this doctoral thesis is primarily attributed to the novelty of a hybrid graphene-catalyst immobilisation-grafting on polyester textile supports for wastewater treatment applications. The final concept of the thesis is to introduce the potential for assembling a fully textile-based reactor for Electro-Fenton wastewater treatments.

This study is developed in collaboration with a small company that works with women's clothing. The company has had recurring problems with the fit of their viscose dress. The purpose of the study is to analyze the effect of the viscose material shrinkage after laundering on the fit of the garment such as balance, ease, length and the garment dimension. Viscose is one of the finest textile materials for dresses sewing because of its properties such as it’s fine shine, drapes well and it have high absorbent. In contrast, viscose material tends to lose strength when wet, which affects garment fit due to viscoses shrinkage after laundering. The study is performed through comparing of three production processes of a dress to get the best fit and dimensions. For sample A and B, the same pattern construction is used, except for sample B, the viscose fabric was pre-washed in advance. While for sample C fabric samples was washed and the number of shrinkage is calculated . Pattern construction was adjusted by adding the results of shrinkage . The three sample dresses were sewn with the same viscose fabric, and the fit were tasted by one person in size Medium .The dress samples were measured both before and after laundering. The result of prototype C showed that the dress has shrunk to the best fit and meets the desired garment sizes in comparison with prototypes A and B. The study showed that garments that are sewn in viscose material change both in fit and size after washing. Washing viscose material before cutting will not ensure that the sewn garment will not shrink or that the garments will retain its dimension after washing. The change in pattern design gives better results.

Smart textiles that have the capability for actuation are of great interest for creating wearables and haptic devices. Through the use of textile fabric production processes electroactive polymeric materials in the form of film-based yarns can be integrated and combined with passive yarns to create soft, actuating fabrics. This way single EAP materials can be transformed into segments consisting of multiple EAP yarns working together. Furthermore, these segments can be positioned within a fabric to work individually or simultaneously in different patterns by use of incorporated conductive yarn paths. While the chase for additivity in force is a long-standing part of developing new actuator structures, so is the need for additivity in displacement motion. Here we construct an actuating textile fabric through the process of weaving that is able to operate in-air using polypyrrole-based tape yarns with choline acetate ionic liquid. Finding the balance between the weaving parameters turned out to be key. We found that in a vertically suspended arrangement, a three-segment serially connected fabric assembly demonstrated an accumulative effect in displacement and a joint-like motion behaviour. This opens up for more complicated motion patterns to be created through textile processing of EAP materials. 

Piezoelectric materials are frequently used in different sensors as they can generate a measurable electrical signal during applied pressure or when subjected to extension. This project examines how a piezoelectric yarn containing Polyvinylidene fluoride (PVDF) is affected when exposed to moisture, heat and long-term mechanical deformation. Focus has been directed towards investigating the properties of the piezoelectric yarn as well as how it can be applied in textile fabrics and textile applications. The piezoelectric yarn has been subjected to a series of tests. Most of the samples have undergone cyclic deformation in an extensometer during tests. The piezoelectric yarn has been examined by experiments in laboratory environment, practical tests in textile applications as well as by statistical analysis. It can be stated that factors such as moisture and temperature have influence on the piezoelectric effect of the yarn. Long-term tests reveal how the yarn displays a change in length while undergoing deformation, which contributes to the diminished signal strength of the yarn. The piezoelectric yarn can successfully be integrated in a piece of fabric by the means of sewing when using correct stitch- length, where higher stitch-length gives a higher signal output. The same method can be applied to construct a piezoelectric sensor used in a training sock. This project can conclude that parameters such as moisture, creep-behaviour and structural variation within the PVDF-filaments have a significant effect on the signal created by the piezoelectric yarn. The potential of the yarn as a sensor can be seen by successfully applying it to a textile structure as well as in a training sock that can monitor the fore and rear foot while running. It can be stated that much remains to be studied in this particular research area regarding piezoelectric filaments and yarns. Further research in the subject will lead to new innovative applications that can be of use in different parts of society, not to say the least in the area of medicine.

The interest in natural fibres as reinforcement for composite materials has been steadily increasing due to their attractive mechanical properties and the possibility of making more eco-friendly materials. Currently, various alternatives are being introduced for commercial applications, as fibres such as hemp, jute and flax exhibit properties, which make them appropriate for structural composite components. Biocomposites offer reductions in weight and cost and have less reliance on foreign oil resources, making them attractive. Several investigations have revealed that the full utilisation of fibre mechanical properties in the final composites can be exploited, provided an aligned fibre orientation is chosen. In fact, a major challenge for natural fibre reinforced composites is to achieve high mechanical performance at competitive prices. The use of commingled/hybrid yarns is one of the more promising methods for manufacturing structural thermoplastic composites.

Commingled yarns of thermoplastic and reinforcing fibres offer a potential for cost-effective production of composite parts, thanks to reduced applied pressures and impregnation times during processing. Besides economic advantages, there is also direct control over fibre placements and ease of handling of fibres in yarn process. The yarn technologies provide homogenous distribution of reinforcing fibre and matrix. Variation in natural fibre properties has been a major problem facing composite manufacturers, compared to carbon and glass fibres that have well-defined production processes. This issue can be addressed by regenerated cellulose fibres. These fibres can be reproduced easily with high surface evenness and even quality, making it possible to get consistent results, which is not possible with natural fibres. Combination of natural and regenerated cellulose fibre brings together the best of both materials. The end result is a product with superior properties, which could not be obtained by the individual components.

This thesis describes the development of aligned hybrid yarns with low fibre twist, for high performance natural (hemp) and man-made (Lyocell) cellulose fibre-reinforced biocomposites, suitable for use in structural or semi-structural applications. The properties of composites in terms of fibre orientation, off-axis angle and alkali treatment were investigated, focusing on determining void%, water absorption, mechanical and thermo-mechanical properties. The results show that combining hemp and Lyocell in PLA composite leads to the reduction of moisture absorption and can improve the mechanical properties. The mechanical properties of the composites were highly affected by the fibre direction. The alkali treatment on hemp fibre improved the mechanical properties of the composites.

This study reports the recycling of discarded denim textiles by the production of all-cellulose composites (ACCs). Discarded denim fabrics were shredded into fibers and then made into nonwoven fabrics by carding and needle punching. The produced nonwoven fabrics were converted to ACCs by one-step and two-step methods using an ionic liquid (IL), 1-butyl-3-methyl imidazolium acetate ([BMIM][Ac]). In this study, the effect of different ACC manufacturing methods, denim fabrics with different contents (a 100% cotton denim (CO) and a blend material (cotton, poly-ester and elastane (BCO)) and reusing of IL as a recycled cellulose solvent on the mechanical pro-perties of the formed ACCs were investigated. The ACCs were characterized according to their tensile and impact properties, as well as their void content. Microscopic analysis was carried out to study the morphology of a cross-section of the formed composites. The choice of the one-step method with recycled IL, pure IL or with a blend material (BCO) had no influence on the tensile properties. Instead, the result showed that the two-step method, with and without DMSO, will influence the E-modulus but not the tensile strength. Regarding the impact properties of the samples, the only factor likely to influence the impact energy was the one-step method with CO and BCO.

In this work, high-performance fibers such as aramid (Twaron), polyamide (PA6), polyester (PET), and hybrid Twaron/PA6 fibers were transformed into electroactive fibers by coating them with conjugated polymer, poly(3,4-ethylenedioxythiophene) (PEDOT) through vapor phase polymerization (VPP) method. The VPP is considered as an efficient technique for depositing CPs on different substrates regardless of their lower solubility in various solvents. In this paper, PEDOT-coated high-performance fibers were prepared under already optimized reaction conditions, and then a comparison between electrical, thermal, and mechanical properties of different fibers, before and after coating, was made. The obtained coated fibers were characterized through scanning electron microscope (SEM), thermogravimetric analysis (TGA), 2-probe electrical resistance measurement method, and tensile testing. It was revealed that at particular reaction conditions, all high performance textile substrates were successfully converted into electroactive fibers. The voltage-current (V-I) characteristics showed that PEDOT-coated polyester fibers exhibited highest conductivity value among all other substrate fibers. The active PEDOT layers on high performance fibers could behave as an antistatic coating to minimize the risks associated with static charges at work places. Also, the obtained fibers have potential to be used as smart materials for various medical, sports, and military applications.

In this work, high-performance fibers such as aramid (Twaron), polyamide (PA6), polyester (PET), and hybrid Twaron/PA6 fibers were transformed into electroactive fibers by coating them with conjugated polymer, poly(3,4-ethylenedioxythiophene) (PEDOT) through vapor phase polymerization (VPP) method. The VPP is considered as an efficient technique for depositing CPs on different substrates regardless of their lower solubility in various solvents. In this paper, PEDOT-coated high-performance fibers were prepared under already optimized reaction conditions, and then a comparison between electrical, thermal, and mechanical properties of different fibers, before and after coating, was made. The obtained coated fibers were characterized through scanning electron microscope (SEM), thermogravimetric analysis (TGA), 2-probe electrical resistance measurement method, and tensile testing. It was revealed that at particular reaction conditions, all high performance textile substrates were successfully converted into electroactive fibers. The voltage-current (V-I) characteristics showed that PEDOT-coated polyester fibers exhibited highest conductivity value among all other substrate fibers. The active PEDOT layers on high performance fibers could behave as an antistatic coating to minimize the risks associated with static charges at work places. Also, the obtained fibers have potential to be used as smart materials for various medical, sports, and military applications.

This thesis explores the possibilities of printing enzymes using resource-efficient technologies to promote the binding of other proteins and biomaterials on synthetic textiles. This strategy can be used to develop advanced textiles for applications, for example, in antimicrobial, drug delivery and biosensing. Digital inkjet printing was combined with enzyme technology to ensure minimum use of water, chemicals and energy in textile manufacturing processes.  

Inks containing two enzymes, lysozyme and tyrosinase, were formulated by adjusting several rheological and ionic properties. The activity of these enzymes was optimised while being printed through two different industrial grade piezoelectric printheads. The theoretical printability of the prepared inks was calculated. The effect of printhead temperature and number of printing passes on the activity was evaluated. Polyester (polyethylene terephthalate) and polyamide-6,6 were pre-treated through several techniques to understand their effect on enzyme adhesion, binding and activity retention. Tyrosinase was used to bind lysozyme on plasma activated polyamide-6,6 surface. The effects of printing these two enzymes in various sequences, i.e. tyrosinase before lysozyme and vice-versa on binding stability and activity, were studied. Influence of the printing process on enzyme kinetics was evaluated. Ability to store and reuse printed fabrics was also studied.  

Lysozyme and tyrosinase containing inks showed activity retention of 85% and 60%, respectively. Activity of lysozyme containing ink was optimum at 10–15 mPa.s when glycerol was used as a viscosity modifier. However, the optimum viscosity for tyrosinase containing ink was at 6–9 mPa.s, and carboxymethyl cellulose was found to be the most favourable modifier. For both inks, a surfactant amount below the critical micelle concentration was considered to be the most effective for printing. Among the studied fabric pre-treatment methods (alkaline, cutinase and plasma), it was found that the activity and stability of the enzyme were dependent on the nature of the pretreatment processes, which can be beneficial for different application areas, e.g. drug release and bio-sensing. Upon printing both inks on a plasma treated polyamide-6,6, tyrosinase was able to catalyse lysozyme protein to bind it on fabric. A maximum of 68% lytic activity was retained by lysozyme when it was printed after tyrosinase. This fabric showed inhibition of bacterial growth and retained almost half of its initial activity when cold stored for a month. 

This chapter provides a comprehensive overview of wet processing techniques in the textile industry, emphasizing sustainability as a core theme. Wet processing encompasses a series of chemical and mechanical treatments that are designed to enhance fabric performance, aesthetics, and usability while addressing the industry's growing responsibility to minimize environmental impacts. The chapter is structured into distinct sections, each highlighting the processes, machinery, and sustainable practices that define modern textile finishing. Each section highlights emerging and alternative technologies along with helpful hints on innovation and marketing opportunities. 

The introduction outlines the scope and importance of wet processing, with a focus on the integration of sustainable technologies and eco-friendly practices in transforming raw textiles into functional and high-quality materials. The pre-treatment section discusses key preparatory steps, including desizing, scouring, and bleaching, and explores sustainable alternatives such as enzyme-based treatments and plasma treatments. The dyeing section examines the application of colour through traditional and innovative methods like foam and spray dyeing. The focus is on reducing resource consumption with approaches like plasma-enhanced dyeing and dyebath reuse. In the printing section, techniques such as screen, rotary, and digital printing are explored, emphasizing sustainable practices like reducing chemical waste through precision and automation. The finishing segment highlights mechanical finishes like compacting, brushing, sanforizing and heat-setting, along with chemical finishes such as water-repellence, flame retardants, anti-microbial properties and decorative denim washing. A focus is placed on using bio-based finishing agents and energy-efficient machinery to align with sustainability goals while enhancing fabric usability.

The structure of this chapter integrates theoretical concepts with industrial practices, offering a balance of scientific understanding and practical application. By the end of this chapter, readers will gain a holistic understanding of wet processing, its impact on textile properties, and its role in meeting industry and consumer expectations.

Children suffering from autism spectrum disorder are often reported to encounter sleeping disorder several causes such as hypersensitivity as a result of irregular brain and muscle functions. Disturbance in sleep affects not only their health but also daytime activities including the risk of other cognitive and behavioral impairments. Such hindrance in sleep has been demonstrated to treat therapeutically by measures like the application of deep pressure touch and full body vibration which can be beneficially integrated into the sleeping environment such as on the textile-based platform around the bed. With such a vision, this pilot design project aimed to develop a smart textile based sleeping bag incorporated with sensors to detect awakening stage of the child and thereby actuating stimuli for assuaging the child to fall asleep. To serve the purpose, a micro-controllable body movement detection sensor, based on conductive yarns connected to a vibrating motor was prosperously embedded at the interior of the sleeping bag along with weighted slots to exert deep touch and soothing sensation in the form of wearable technology.

The emergence of multi-resistant bacteria, untreatable with conventional medicines, is a significant global health concern. This study proposes a unique solution to this problem by digitally inkjet printing biomaterials bound with silver nanoparticles (NP) on cotton textiles. The silver nanoparticles, known for their effective antimicrobial properties, are stabilized, and made biocompatible by the enzymes. The use of digital inkjet printing allows for precise application of these NP-biomaterial conjugates, ensuring uniform coverage and optimal performance. This approach aims to prevent the spread of antimicrobial-resistant bacteria through cotton textiles in medical care environments, enhancing patient safety. The inkjet printing technology used in this study offers high-resolution patterning, enabling the creation of complex designs with multiple materials. This flexibility allows for the development of textiles with varying antimicrobial properties, tailored to specific applications in the medical field. Furthermore, the use of cotton, a natural and breathable material, ensures the comfort and safety of patients, making it an ideal choice for this application.

Lysozyme was inkjet printed on two different polyester fabrics considering several challenges of printing enzymes on synthetic fabric surfaces. Wettability of both the fabrics were improved by alkaline pre-treatment resulting reduction in water contact angle to 60±2 from 95°±3 and to 80°±2 from 115°±2 for thinner and coarser fabric respectively. Activity of lysozyme in the prepared ink was 9240±34 units/ml and reduced to 5946±23 units/ml as of collected after jetting process (before printing on fabric). The formulated ink was effectively inkjet printed on alkali treated polyester fabric for antimicrobial applications. Retention of higher activity of the printed fabric requires further studies on enzyme-fibre binding mechanisms and understanding protein orientation on fabric surface after printing

Enzymes immobilized on synthetic polyethylene terephthalate (PET) textile surface by resource‐efficient inkjet printing technology can promote developments for various novel applications. Synthetic fabrics often require adequate pretreatments to facilitate such printing process. This work discusses PET–woven fabric pretreatment routes to improve wettability by alkaline, enzymatic, and plasma processes for effective printing of lysozyme using an industrial piezoelectric printhead. Results indicate that all pretreated samples contain a similar amount of enzymes upon printing. Plasma treated fabrics show relatively more hydrophilic surface characteristics, better protein binding stability, and lower retained activity. Alkali and cutinase‐treated samples possess relatively higher activity due to the greater amount of enzyme desorption to substrate solution. Depending on respective enzyme‐binding stability, a combination of a well-pretreated surface and inkjet as preferential placement technology, the approach of this study can be used as a facile enzyme immobilization method for suitable applications, for example, controlled‐release and bio‐sensing.

Inkjet printing of enzymes can facilitate many novel applications where a small amount of materials need to be deposited in a precise and flexible manner. However, maintaining the satisfactory activity of inkjet printed enzyme is a challenging task due to the requirements of ink rheology and printhead parameters. Thus to find optimum inkjetting conditions we studied the effects of several ink formulation and jetting parameters on lysozyme activity using a piezoelectric printhead. Within linear activity range of protein concentrations ink containing 50 µg/mL lysozyme showed a satisfactory activity retention of 85%. An acceptable activity of jetted ink was found at pH 6.2 and ionic strength of 0.06 molar. Glycerol was found to be an effective viscosity modifier (10–15 mPa.s), humectant and protein structure stabilizer for the prepared ink. A non-ionic surfactant when used just below critical micelle concentration was found to be favourable for the jetted inks. An increase in activity retention was observed for inks jetted after 24 hours of room temperature incubation. However, no additional activity was seen for inkjetting above the room temperature. Findings of this study would be useful for formulating other protein-based inks and setting their inkjet printing parameters without highly compromising the functionality.

Immobilization of enzymes on textiles can impart a range of advanced applications e.g. anti-microbial, controlled release, drug delivery and bio-sensing (Wehrschütz-Sigl et al., 2010). Such applications enable minimal consumption, recovery, and reusability of these valuable bio-materials compared to their conventional textile applications in surface cleaning and finishing (Araujo et al., 2008). Methods used for immobilization can play important roles to ensure precise, flexible and contamination free application. Compared to many of the conventional methods of textile immobilization such as coating and screen-printing, digital inkjet technology offers many benefits for such advanced applications (Kan and Yuen, 2012). Among various inkjet technologies, drop-on-demand piezoelectric printing is a promising resource-efficient technology for enzyme immobilization. 

The enzymes should retain high activity after the immobilization process. Various factors involved during inkjet printing (Saunders and Derby, 2014) and fabric characteristics (Mohamed et al., 2008) can influence this enzymatic activity. Factors concerning the inkjet procedure include rheology and ionic nature of ink along with the shear force and waveform generated inside a piezoelectric printhead (Magdassi, 2010). Factors dependent upon fabric characteristics include surface structure, pore size distribution, and binding mechanism (Nierstrasz and Warmoeskerken, 2003). In this work, we have studied the effects of inkjet procedures on enzymatic activity. Lysozyme being a stable and well-studied enzyme was chosen for our experiments. A Xennia Carnelian printer with a Dimatix QS10 industrial printhead was used for inkjetting. Lytic activity of lysozyme was studied by a UV-Vis spectrophotometer against decrease of Micrococcus lysodeikticus cell concentration at 450 nm. Results showed ca. 10-15% activity reduction of the jetted lysozyme ink. As all the ink and printer parameters were optimized, the probable reason for such reduction could be the effect of shear forces inside the printhead on three-dimensional conformation of lysozyme. In conclusion, our formulated lysozyme ink showed potential for printing textiles with probable activity reduction that require further investigation. 

Enzymes can be immobilized on textiles to impart anti-microbial properties in a more environment-friendly manner compared to conventional biocide-based solutions. Such application requires ensuring precise, flexible and contamination-free immobilization methods that can be offered by digital printing compared to coating or screen-printing techniques. Drop-on-demand inkjet printing is a resource-efficient technology that can ensure these requirements. The use of polyester and polyamide-based fabrics is rising for applications ranging from apparel and home furnishing to hygiene and medical textiles. These fibers offer superior chemical, physical, and mechanical properties due to their inert nature but challenge the printing process due to hydrophobicity and lack of functional groups. Lysozyme and tyrosinase are two enzymes showing great potential for grafting on synthetic fabrics paving the way to use them for inkjet printing as well.

Challenges for inkjet printing of enzymes on synthetic fabric surfaces come in multiple forms i.e. ink recipe formation, printer mechanics and fabric surface characteristics. The ink must maintain a suitable viscosity and surface tension for effective drop ejection and a feasible ionic nature for enzyme activity. Then, the enzyme must be able to sustain the temperature and shear stress generated inside an inkjet printhead. Finally, influential fabric characteristics include surface structure, pore size distribution, evaporation rate and binding mechanism. By considering these parameters, lysozyme and tyrosinase were successfully printed on variously modified synthetic fabrics using a combination of sustainable technologies.

Tyrosinase enzyme was digitally printed on plasma pretreated polyamide-6,6 fabric using several sustainable technologies. Ink containing carboxymethyl cellulose was found to be the most suitable viscosity modifier for this enzyme. Before and after being deposited on the fabric surface, the printed inks retained enzyme activity of 69% and 60%, respectively, compared to activity prior printing process. A good number of the printed enzyme was found to be strongly adsorbed on the fabric surface even after several rinsing cycles due to surface activation by plasma treatment. Rinsed out fabrics retained a maximum activity of 34% resulting from the well-adsorbed enzymes. The activity of tyrosinase on printed fabrics was more stable than ink solution for at least 60 days. Effects of pH, temperature and enzyme kinetics on ink solution and printed fabrics were assessed. Tyrosinase printed synthetic fabrics can be utilized for a range of applications from biosensing and wastewater treatment to cultural heritage works.

Recognise my value and keep me a while longer is an exploratory project in sustainable textile design. The focus is to explore possible design solutions that can give products a property transformation over time and prolong the products life cycle. This through practical investigations with different materials based on a chosen approach to sustainable design and changeable pattern images. Also with aim to give the consumer an active role in the changing of a products appearance and function. The end result is three product prototypes that all in different ways exemplify the chosen approach to sustainable design. 1. Moss is a jumper made of circular knitted jacquard fabric with the material combination Sally Fox cotton and unbleached cotton. The fabric is conformable and soft with a pattern that changes hue strength for each time the consumer washes it. The changing pattern makes the jumper interesting because it´s expression changes slowly while it´s being used. 2. Cone is a duvet and pillow cover that is made of a five shed satin jacquard weave. The textile pattern and colour is inverted on the back and front side of the textile. The aesthetic expression of the bed clothing can be renewed by the consumer through vegetable dyes. 3. Bark is a flat knitted, dubble relief, jacquard wool blanket. The blanket can be transformed by the consumer, through washing, and then get a new function as a rug. The textile goes from a soft, two-dimensional, flexible and somewhat fragile textile into a compact, three-dimensional durable textile.

In electronic textiles, we apply production techniques from both textiles and electronic engineering to bridge the gap between these two very different materials. While it is obvious to apply electronic engineering to textiles to ensure the working of the electronic components, the application of textile production techniques to electronics is still challenging. Yet it is in the appropriation of textile manufacturing that there is a huge potential for innovation. This potential does not only cover the means of production, but also the way we interact with digital interfaces as well as the overall aesthetic of those interfaces.

This report documents the application of textile production techniques for sensing and actuation in e-textile structures and artifacts. It shows how weaving and knitting on industrial machines can be used to design and build electronic elements in a textile shape, such as pressure sensors, speaker coils and shape change structures. The report also documents the application of those techniques in two different prototypes, the first being a sensor glove that was used for gesture recognition, and the second being woven textile muscle that was developed as the basis for a soft textile robot.

Textiles are pervasive in our life, covering human body and objects, as well as serving in industrial applications. In its everyday use of individuals, smart textile becomes a promising medium for monitoring, information retrieval, and interaction. While there are many applications in sport, health care, and industry, the state-of-the-art smart textile is still found only in niche markets. To gain mass-market capabilities, we see the necessity of generalizing and modularizing smart textile production and application development, which on the one end lowers the production cost and on the other end enables easy deployment. In this chapter, we demonstrate our initial effort in modularization. By devising types of universal sensing fabrics for conductive and non-conductive patches, smart textile construction from basic, reusable components can be made. Using the fabric blocks, we present four types of sensing modalities, including resistive pressure, capacitive, bioimpedance, and biopotential. In addition, we present a multi-channel textile–electronics interface and various applications built on the top of the basic building blocks by ‘cut and sew’ principle.

An industrial dyeing process in supercritical carbon dioxide has been modelled with computational fluid dynamics using Ansys Fluent software. In order to investigate the distribution of the dye carrier fluid, the flow resistance of the fabric has been accurately characterised. For this purpose, in the first part of the work a plain-woven fabric geometry was created in the open software Tex-Gen and modelled in Ansys Fluent to predict the permeation of fluid through the pores of the fabric material and to estimate the relationship between local fluid velocity and pressure drop. The second part of the study focused on evaluating the influence of beam structure, inlet flow rate, fabric height on the fluid flow through the fabric, which must be uniform to achieve a homogeneous level of dyeing. From the simulations the main obstacle to achieving a uniform flow velocity in the fabric is the pressure rise that occurs in the beam and creates a slight difference in permeation velocity between the two axial ends of the fabric; other disturbances, such as the effect of the perforated structure of the beam, are usually minor. Due to the low viscosity of supercritical carbon dioxide, inertial losses predominate over viscous losses in the porous medium. This means that approaches based only on the permeability of the fabric and the application of Darcy's law are inadequate to correctly predict the response of a dyeing unit when using carbon dioxide.

The aim of this project was to create a sensor in textile material which can register and recognize different kinds of pressure. A suitable method has been developed in order to scientifically investigate and evaluate the sensitivity of the prototypes. The prototypes have been produced with a computerized hand weave machine and the materials used were polyester and piezoelectric PVDF-fiber, twisted with a conductive yarn, Shieldex®. When a force is applied to the PVDF-fiber, causing an extension of the fiber, a voltage is generated directly related to the applied force. The final prototype is a woven textile with integrated monofilaments and weft inserted in seven different layers to create a voluminous structure. An extension by the PVDF-fiber is there by enabled to occur which is related to the force applied onto the structure.

Three equable prototypes were produced, each consisting four separated PVDF-fibers which were inserted with a distance of 1, 5 cm from each other. The prototypes were further attached one by one on a homemade ramp and the PVDF- and Shieldex®-fibers were connected to an oscilloscope. Different weights were then rolled from the top of the ramp, generating a voltage each time it pressures a fiber, which were seen on the computer software of the oscilloscope. The results were afterwards analyzed and evaluated using Excel.

A clear relationship between applied force and generated voltage is shown although there is a great variety among the test results on each weight along with large standard deviations. The exact weight generating a specific voltage is therefore difficult to determine.

To achieve the ultimate potential of circular economy (CE), cascading plural circular business models (CBMs) can essentially slow down, narrow, and close resource loops while simultaneously achieving long-life products. Operating in cascades, however, organizations face many paradoxical tensions (PTs) due to different goals, designs, and resource requirements, as well as demands for new and unusual collaborations. Having a narrative literature review, 7 categories of PTs that could hinder scaling CBMs in cascaded systems in the textile and clothing (T&C) industry were identified. Conducting 20 semi-structured interviews with European brands/retailers, charities (secondhand stores), sorters, and recyclers who operate in cascading, this paper has contextualized four paradox classes (organizing, performing, belonging, and learning) of Smith and Lewis’s (2011) paradox theory framework along those 7 categories; while mostly classified as organizing and performing, categories 5 (between circular supply structure and governance alternatives) and 1 (between scale and scope) are reported as the most prominent among T&C actors, respectively. Although those prominent categories can directly hinder the scalability of cascading CBMs, those that appeared internally and were associated with a particular CBM could indirectly affect scaling.

To achieve the ultimate potential of the circular economy (CE), it is necessary to operationalize a cascaded system where R-imperative business models such as repair, reuse, and recycling are implemented before the materials/products end up in energy recovery. Despite frequent discussions of the cascade, mainly in the case of biological nutrients, there is a dearth of literature on understanding cascading for technical material/product cycles. Given the resource-intensive and polluting nature of textiles and clothing (T&C) industry, thus cascading can play an important role. This study, through a systematic literature review, attempts to understand the facilitators and barriers to cascade circular business models in the T&C industry. Results indicate different closed loops cascading between the downstream actors of the value chain where brands and service providers are involved. Likewise, between manufacturers and recyclers engaged in downcycling activities. The cascades have also been seen in open loops, in the inter-industrial forms, such as the production of composite materials and building insulation from textile waste and non-woven textiles. In particular, the non-participation of the brand owner in the valuation of used clothes, lack of markets and recyclers in the care of textile waste, and effective recycling policies to ensure high quality in recycling are among the most important cascade barriers while structured provision of information, government financial support, and deliberate actions by the economic policymakers can facilitate cascading. This study provides a basis for further collaboration between T&C value chain actors in capturing undiscovered implicit and explicit values in the transition to CE.

In this collection I have explored the paradox of perfection. The collection is an epic tribute to my prior self and discovers how the unperfect can be transformed to something, perceived, perfect. I flirt with my past obsessions in finding mathematically measured legs, exact tailored arms and perfectly fitted stockings. In a fun, poetic and melancholy way I invite the viewer on a highly visual voyage to my childhood where the obsession of finding costume perfection "Vemoden" the act of control becomes visual through statuesque frozen looks, where the previous unperfect becomes perfection.

The relationship between technology and the expression of form have always been interconnected in the architectural design process; associating the art of envisioning spaces with the craft of materializing them. Recently in terms of surface fabrication, computational tools of representation and material fabrication opened for architectural design new possibilities to explore novel spatial expressions. Surface design processes in architecture start to borrow from the logic of representation of different non-hierarchical structures, e.g., biological systems or textile construction techniques. Relating to that, the present fascination of textiles in architectural design relies on this specific way of building surface design as non-hierarchical form, and by that, allowing the designer to play with the depth of the surface design at micro and macro levels. Exploring different relations between digital and physical through textiles expressions, this research reassess static principles of form–marking the turn from static to relational principles. Thus, the intention is to describe how the character of the textiles and computation as design material redefines the notion of space trough surface aesthetics merging the digital to the physical, and how spatiality can be questioned through textile and interaction aesthetics. Using practice-based research methodology, this research opens and explores this design space by relating theory and practice; it questions and reframes fundamental concepts of expression and scale in architecture by proposing methods for surface design, and a specific language to describe textile architectural aesthetics.

As a way of opening a space where methods from the fields of fashion design, textile design and interaction design overlap, the project Repetition intersects different methodologies through practice-based research in design. Experiments were conducted to explore ways of creating relationships between body and space by means of translating information as pattern design between garments and interactive knitted walls. By arranging a startup performance, we reflected on the expressional variables that influence the expression of the pattern translations; variables concerning the garments, the walls, the print and the movements were illustrated by the expressions found. The result formulates specific descriptions regarding accuracy and distribution of pattern translation, illustrating basic concepts of pattern formations identified in visual changes appearing in the garment. By communicating our understanding of basic expressions, Repetition aims to formulate a new framework for collaborative work as a method for further design.

Hospital-acquired infections have become a major challenge which threaten the hospitalized patients’ safety. The presence of nosocomial pathogens is generally reported in connection with solid surfaces near patient environments. These surfaces become significant sources of transmission and lead most often to the contamination and cross-contamination of nosocomial pathogens to the patients and staff. This paper investigates strategies to apply beneficial bacteria on viscose-based nonwoven wipes and the viability of these beneficial bacteria on the wipes along with characterization of the physical properties of the wipes. Major findings include that it is possible to produce dry wipes which contain an adequate number of beneficial bacteria or spores. After these wipes are wetted, they can release a certain number of bacteria from the wetted wipes. These released beneficial bacteria can inhibit pathogens by growing and colonizing on the wiped surfaces.

Adopting circular economy approaches is becoming an increasingly important part of policy makers’ agendas in the fight against climate change. These approaches include reducing material inputs, using more environmentally friendly and reusable materials when producing goods, ensuring materials are properly recycled, and minimizing waste and pollution. They have become even more important in the wake of the COVID-19 pandemic, with personal protective equipment (PPE) becoming an inseparable part of daily life. Manufacturers across the globe had to increase PPE production, which inevitably created a surge in plastic waste because polypropylene is still the main material used to manufacture PPE for health-care workers. A recent research study estimates that, since the outbreak, the amount of plastic waste generated globally is 1.6 million tons per day.Furthermore, an estimated 3.4 billion single-use face masks and shields are being discarded every day. This unpredicted increase in plastic waste is happening at a time when countries are reluctant to recycle products because of the lack of complementary decontamination steps and coordination in waste management.Some manufacturers took this opportunity of increased PPE production to adopt circular economy approaches that can be replicated by others. Decentralized production and material sourcing became more important as supply chains were severely disrupted by the pandemic. This has accelerated the ongoing changes in conventional production methods, with businesses embracing a cradle-to-cradle manufacturing model—that is, rethinking the design of their products from the starting point at the sourcing stage through to the end of the product’s life.

This is not without its challenges. For example, when replacing plastics with alternative materials, manufacturers need to ensure that these materials meet quality standards set by standards institutions and enforced by governments.However, PPE manufacturers cannot shoulder the responsibility of the global plastic waste challenge alone. This publication calls on a broad range of stakeholders along the PPE value chain to work together to shift toward a more sustainable and circular PPE ecosystem.This report takes stock of approaches that PPE manufacturers are taking to make their production more sustainable and achieve a true circular economy, while responding to COVID-19 PPE shortages. It does not provide a life-cycle assessment of each PPE product, which is needed to evaluate the environmental effects associated with each product against the benefits created. The approaches highlighted in this report can be grouped into four main categories:

•Circular inputs: The use of renewable, bio-based, or completely recyclable materials as input.

•Resource recovery: Ensuring that useful resources and energy are recovered from disposed products by collecting and reprocessing products at the end of their life.

•Product use extension: Prolonging the lifespan of PPE products by choosing a design that allows the product to be repaired or by choosing durable materials as inputs for the main PPE parts.

•Product as service: The product-as-service model allows the consumer to use a product that is retained by the producer to increase resource productivity (for example, leasing PPE). This model allows PPE manufacturers to move from selling products to selling services.

Electronic textiles (E-textiles) are made using various materials including carbon nanotubes, graphene, and graphene oxide. Among the materials here, e-textiles are fabricated with reduced graphene oxide (rGO) coating on commercial textiles. rGO-based yarns are prepared for e-textiles by a simple dip coating method with subsequent non-toxic reduction. To enhance the conductivity, the rGO yarns are coated with poly(3,4-ethylene dioxythiophene): poly(styrenesulfonic acid) (PEDOT) followed by electrochemical polymerization of polypyrrole (PPy) as the electromechanically active layer, resulting in textile actuators. The rGO-based yarn actuators are characterized in terms of both isotonic displacement and isometric developed forces, as well as electron microscopy and resistance measurements. Furthermore, it is demonstrated that both viscose rotor spun (VR) and viscose multifilament (VM) yarns can be used for yarn actuators. The resulting VM-based yarn actuators exhibit high strain (0.58%) in NaDBS electrolytes. These conducting yarns can also be integrated into textiles and fabrics of various forms to create smart e-textiles and wearable devices. 

Recently, electrically driven conducting polymer (CP) coated yarns have shown great promise to develop soft wearable applications because of their electrical and mechanical behaviour. However, designing a suitable yarn actuator for textile-based wearables with high strain is challenging. One reason for the low strain is the voltage drop along the yarn, which results in only a part of the yarn being active. To understand the voltage drop mechanism and overcome this issue intrinsically conductive yarns were used to create a highly conductive path along the full length of the yarn actuator. Ag plated knit-de-knit (Ag-KDK) structured polyamide yarns were used as the intrinsically conductive core material of the CP yarn actuators and compared with CP yarn actuators made of a non-conductive core knit-de-knit (KDK) yarn. The CP yarn actuators were fabricated by coating the core yarns with poly(3,4-ethylene dioxythiophene): poly(styrene sulfonic acid) followed by electrochemical polymerization of polypyrrole. Furthermore, to elucidate the effect of the capillarity of the electrolyte through the yarn actuator, two different approaches to electrochemical actuation were applied. All actuating performance of the materials were investigated and quantified in terms of both isotonic displacement and isometric developed forces. The resultant electroactive yarn exhibits high strain (0.64 %) in NaDBS electrolytes as compared to previous CP yarn actuator. The actuation and the electroactivity of the yarn were retained up to 100 cycles. The new highly conductive yarns will shed light on the development of next-generation textile-based exoskeleton suits, assistive devices, wearables, and haptics garments.

Flax is a traditional plant used to make textiles. Flax, like all natural fibres, is a material with variations. Knowledge of a crafting process can be obtained by studying artefacts and all available documentation and by being present in a craft tradition and society of spinning. A craftsperson will make many small decisions during their work. How do we gain knowledge about handling materials, and how do we preserve the intangible skills relevant to a craft? This performance article aims to make visible specific knowledge of material, tools and working methods for re-hackling flax. The text and performance illustrate the perspective of a reflecting craftsperson. By asking questions about the work process, critical decisions regarding crafts will be highlighted. This approach will help preserve and transmit craft skills within flax processing.

The following have been rectified in response to previous evaluation by examiner Olof Bruninge. -We have solely chosen qualitative methods in data collection and analysis by making use of data gathered from focus group workshop. The findings have been coded and analysed descriptively. -We have reformulated research questions and replaced the hypothesis with open questions. Allowing us to explore the participants’ behaviour rather than testing hypothesis. -All quantitative measures have been replaced with qualitative analysis and descriptions. -We have provided tables with results from focus group findings to increase transparency in our data

The number of 3D textile applications in medicine is rapidly increasing as new technology and procedures are introduced in health care.  A first estimate of current medical applications of both general and 3D textiles is presented based on the medical devices classification system established by the US Food and Drug Administration. The textile specifics for these applications are covered from a textile technique perspective where the different 3D weaving as well as knitting, braiding and non-woven techniques are described and how their properties they can contribute in medical applications. In addition, emerging opportunities based on smart textiles as part of textile systems are described on a general level. The strong application areas of 3D medical textiles, i.e. wound management, vascular grafting and scaffolding for tissue engineering are covered in detail both from the medical and textiles perspective. Finally, some future lines of development are suggested and a short discussion on how new 3D textiles applications can be developed in close cooperation between the textile industry and the health care sector is presented.

Electrical stimulation can be used for the treatment of various nerve and muscle injuries as well as acute and chronic pain conditions. An electrical pulse is applied to a muscle or nerve to activate excitable tissue using internal or external electrodes with the aim of building muscle strength, artificially creating or supporting limb movement or reducing pain. Textile electrodes offer several advantages over conventionally used disposable surface electrodes: they are flexible and re-usable and they do not require hydrogels, thereby avoiding skin irritation and allergic reactions and enhancing user comfort. This article presents a literature review that assesses the state of research on textile electrode constructions. Based on the review, production approaches and designs are compared, methods for evaluating stimulation discomfort and pain are proposed and issues related to user compliance are discussed. The article concludes with suggestions for future work focused on investigating the impacts of textile-based electrode parameters on comfort, convenience and ease of use.