Electronic Textiles: Properties, Types, Manufacturing and Applications
Sikander Anwer
Department in Textile Engineering
University of Management & Technology, Lahore, Pakistan
Email: 111811016@umt.edu.pk
History: Electronics in textiles is an emerging interdisciplinary field of research that brings together specialists in information technology, microsystems, materials and textiles. E-textile is short for electronic or electro-textile. E-textiles are also called conductive clothing, electronic clothing, and soft circuits. The wearable electronic textiles arena has generated a massive demand and significant opportunities stem from increased consumer demand for lightweight electronic devices integrated with clothing.
At the end of the 19th century, as people developed and grew accustomed to electronic appliances, designers and engineers began to combine electricity with clothing and jewelry developing a series of illuminated and motorized necklaces, hats, broaches and costumes. For example, in the late 1800s, a person could hire young women adorned in light-studded evening gowns from the Electric Girl Lighting Company to provide cocktail party entertainment.
In 1968, the Museum of Contemporary Craft in New York City held a groundbreaking exhibition called Body Covering that focused on the relationship between technology and apparel. The show featured astronauts’ space suits along with clothing that could inflate and deflate, light up, and heat and cool itself. Particularly noteworthy in this collection was the work of Diana Dew, a designer who created a line of electronic fashion, including electroluminescent party dresses and belts that could sound alarm sirens.
In the mid 1990s a team of MIT researchers led by Steve Mann, Thad Starner, and Sandy Pentland began to develop what they termed wearable computers. These devices consisted of traditional computer hardware attached to and carried on the body. In response to technical, social, and design challenges faced by these researchers, another group at MIT, that included Maggie Orth and Rehmi Post, began to explore how such devices might be more gracefully integrated into clothing and other soft substrates. Among other developments, this team explored integrating digital electronics with conductive fabrics and developed a method for embroidering electronic circuits.
Introduction: Electronic textiles, or simply e-textiles, are textiles with embedded electronics and some fiber materials possessing electrical characteristics and providing some useful functions. An electronic textile is a fabric that can conduct electricity. If it is combined with electronic components it can sense changes in its environment and respond by giving off light, sound or radio waves.. Electronic textiles (e-textiles) are fabrics that have electronics and interconnections woven into them. Components and interconnections are a part of the fabric and thus are much less visible and, more importantly, not susceptible to becoming tangled together or snagged by the surroundings. An electronic textile refers to a textile substrate that incorporates capabilities for sensing (biometric or external), communication (usually wireless), power transmission, and interconnection technology to allow sensors or things such as information processing devices to be networked together within a fabric. Electronic textiles allow little bits of computation to occur on the body. They usually contain conductive yarns that are either spun or twisted and incorporate some amount of conductive material (such as strands of silver or stainless steel) to enable electrical conductivity.
Definition: E-textiles, also known as electronic textiles or smart textiles, are fabrics that enable digital components (including small computers), and electronics to be embedded in them.
Properties of e-textiles:
Flexible
No wires to snag environment
Large surface area for sensing
Invisible to others
Cheap manufacturing
Permeability
Strength
Thermal Resistance
Electrical resistance
Types of electronic textiles: The field of electronic textiles can be divided into two main types:
Electronic textiles with classical electronic devices such as conductors, integrated circuits, LEDs, and conventional batteries embedded into garments.
Electronic textiles with electronics integrated directly into the textile substrates. This can include either passive electronics such as conductors and resistors or active components like transistors, diodes, and solar cells.
Most research and commercial e-textile projects are hybrids where electronic components embedded in the textile are connected to classical electronic devices or components. Some examples are touch buttons that are constructed completely in textile forms by using conducting textile weaves, which are then connected to devices such as music players or LEDs that are mounted on woven conducting fiber networks to form displays. Printed sensors for both physiological and environmental monitoring have been integrated into textiles including cotton, Gore-Tex, and neoprene.
Manufacturing of Electronic Textiles: A thread can be made to conduct electricity by either coating it with metals like copper or silver. It can also be made conductive by combining cotton or nylon fibers with metal fibers when it is spun.
Inputs for electronic textiles:
To obtain information for wearable devices components such as sensors are often used, for instance, environmental sensors, antennas, global positioning system receivers, sound sensors and cameras. Such sensors can be divided on active and passive (Langenhove & Hertleer, 2004)(Seymour, 2009). Active inputs are controlled by a user via a tactile or acoustic feedback system, which provides an intuitive interaction with the garment. Passive inputs collect biometric data from the human body as well as environmental data collected via wireless transmission system.
Construction of electronic textiles:
Lily Pad Arduino
Fabric kit.
Aniomagic
Flora
Conductive fabrics and textiles are plated or woven with metallic elements such as silver, nickel, tin, copper, and aluminum these are: electro-nylon, electr-onylon nickel, clear-mesh, soft-mesh, electro-lycra and steel-cloth. All these textiles show amazing electrical properties, with low surface resistance15, which can be used for making flexible and soft electrical circuits within garments or other products, pressure and position-sensing systems. They are lightweight, flexible, durable, soft and washable (some) and can be sewn like traditional textiles, which makes them a great replacement for wires in computational garments.
Conductive threads and yarns have a similar purpose to wires and that is to create conductive paths from one point to another. However, unlike wires they are flexible and can be sewn, woven or embroidered onto textile, allowing for soft circuits to be created. Conductive threads and yarns offer alternative ways of connecting electronics on soft and flexible textiles medium as well offering traditional textile manufacturing techniques for creating computational garments.
Fig: Conductive threads
Conductive coatings are used to convert traditional textiles into electrically conductive materials. The coatings can be applied to different types of traditional fibers, yarns and fabrics, without changing their flexibility, density and handling.
Conductive ink is an ink that conducts electricity, providing new ways of printing or drawing circuits. This special ink can be applied to textile and other substrates. Conductive inks contain powdered metals such as carbon, copper or silver mixed with traditional inks.
Advancement: Some of the most advanced functions that have been demonstrated in the lab include:
Organic fiber transistors: The first textile fiber transistor that is completely compatible with textile manufacturing and that contains no metals at all.
Organic solar cells on fibers
Applications of Electronic Textiles:
The use of fabric as station to deploy electrical components results in wearable electrical/ computing devices. Early electric and electronic textiles had components added to existing garments. Later, functionality was added by incorporating conducting yarns into fabrics to produce sensors, switches, and actuators.
EXO Technologies has developed heated gloves for use by skiers, motorcyclists, and the military. The heating elements are knitted from novel polymeric FabRoc yarn.
Fig: EXO heated glove
The main important stakeholders for wearable electronics in textiles are end users and a short overview of the major application of wearable electronics is given as under:
1. Retailer Support
A successful embedded electronics for retailer support should cover the needs in logistics, such as stock control, quality insurance control and anti-theft protection. For this purpose, there are several integrated RF indent-tags already in use. These tags consist mainly of an RF antenna used to transfer energy to the indent-tag and to establish a communication link between the tag and the control equipment. The most primitive tags consist of a simple antenna-capacitor resonance circuit. The more complex ones contain simple micro-controllers and non-volatile memories.
2. Service Support
Service support is more important in developed countries like Europe and United States. Here consumer tends to sort clothes into different categories before washing. Therefore, the washing machines are able to treat the clothes in very different ways. Naturally, it happens rarely that a black sock is hiding in a white shirt. This results in coloured shine on the originally white clothes. The consumer can avoid such accidents if the washing machine recognizes type, number and required optimal treatment of the clothes to be washed. In case of conflict, an error message is generated.
3. User Convenience
Built-in electronics may control and support more advanced textile functionalities like temperature, moisture, etc. For that purpose, secure heating and cooling elements are necessary.
Fig: Smart clothes
4. User Interfacing
User interfacing enables the interfacing between the user and electronic belongings or external (out of body) networks and terminals. Sound, gesture and temperature may control such interfaces. Suitable components are microphones, loudspeaker, textile keyboards, flexible displays and more complex devices.
5. Appliance Networking
The networking between different electronic modules is a key feature necessary for the application of user interfaces. One scenario might be the connection of a cellular phone ported in the right pocket, with a personal digital assistant (PDA) in the left pocket, Bluetooth interface in the trousers and the user interface integrated into the coat.
6. Networking with External Networks
The networking with external networks can be done in real time or by batch processing, online and offline. Another offline method might be the use of exchangeable storage elements like multimedia cards, etc. Wearable computers have the potential to enhance the day-to-day activities of the user.
There are also lots of scopes and application is going on around the globe in the recent area due to its state-of-art and portable quality. Now electronic textiles are widely used in military applications, medical applications, fashion and accessories. In current pandemic situation (Covid-19) where thermal scanning is an important aspect, temperature sensing integrated textile can be very useful for detecting fever of any individual.
References:
Electronic Textiles: Smart Fabrics and Wearable Technology Edited by Tilak Dias
Electronics in Textiles and Clothing: Design, Products and Applications by L. Ashok Kumar, C. Vigneswaran
High-Performance Apparel: Materials, Development, and Applications Edited by John McLoughlin, Tasneem Sabir
Founder & Editor of Textile Learner. He is a Textile Consultant, Blogger & Entrepreneur. He is working as a textile consultant in several local and international companies. He is also a contributor of Wikipedia.
