Active Smart Textile Materials:
Active textiles are those clothes that provide care, freshness, comfort and protection for your skin. Active textiles bring new possibilities to your fashion concepts and collections. The principle of active textile is simple: Build active ingredients into the fabric of clothing so that with the natural movement of your body, your skin is slowly freshened and revitalized. A classic example of active textiles is sportswear. Active textiles adapt and change their functionality in response to the external environment. For that reason, active sportswear should provide sufficient heat transfer for the skin temperature to remain within a comfortable range.
Active smart textiles means clothes that adapt and change their functionality in response to changes in the external environment or in response to a user input, be it motion or weather. These textiles may change shape, store and regulate heat, as well as other functions. Among the most common applications of active textiles is in outerwear; specifically, garments that regulate the body’s temperature. In this article I will discuss different active smart textile materials properties and uses.
Properties and uses of different active smart textile materials are described below:
Wearable Electronics:
Quantum Tunnelling Composite (QTC) is a combination of metal composites, such as carbon, steel, nickel and silver, and an insulating binder that conducts electricity when under pressure. Without pressure, the conductive materials are too far apart to allow a current to pass through; when pressure is applied, the conductive materials move closer together and the electrons can tunnel through the insulating material to form an electrical current. QTC is sensitive to a number of stimuli, such as electromagnetic radiation, pressure, sound, vibration, temperature and voltage; these power sources can be either static or portable, including solar power. Solar panels are strong, lightweight, aluminium voltaic panels that are placed on flexible, fabric sleeves to preserve the object’s utility e.g. placed onto the outside of a rucksack. They can generate up to 4watts of power. Incorporating QTC within textile products has revolutionized many industries, including military, aeronautical, medical, sportswear and consumer electronics.
Properties related to most wearable electronics:
- Electrical Resistance; changes from 10¹²Ω to < 1Ω
- Rugged: switches and sensors are reliable and will operate in rough environments
- Functional
- Decorative
- Easy to use
- Comfortable
- Unobtrusive in clothing
- Washable
- Usable when working or moving
- Easily Accessible.
Variations:
- Conductive Printing Inks: Conductive printing inks allow electrical active patterns to be printed directly onto fabric and used where an electrical circuit is required. Printed areas can be switches or pressure pads to start the circuit which can be used in telephone’s touch screen and MP3 players.
- Piezoelectric Materials: These act as pressure or force sensors. They produce an electrical charge in response to some form of compression. They can also be used to create kinetic energy that can be stored for later use. They may be used in trainers to charge mobile phones, GPS units, fabric keyboards, electric guitars, medical monitors and wireless broadband.
Uses of electronic textile:
1. Education: Interactive games; such as touch screens that play sounds when pictures are touched, play mats for babies, height charts etc.
2. Sports: Self-defence training; showing the force of a strike on a training dummy used in martial arts, for example. Athletes’ shoes can record their foot pressure distribution over time to evaluate movement and weight relationships on different running surfaces. They are also used to monitor breathing and heart rate whilst training.
3. Medical: Blood pressure cuff, monitors pressures and tensions for bandages and casts. Monitors respiration, CPR chest compressions can be measured and prompts to administer CPR. Measure hand grip strength for muscular fatigue studies. Monitors on suits to measure levels of nitrogen etc in the air. Prosthetic hands have a sensing textile skin.
4. Health and Safety: Monitors to determine the ergonomics of car seats for anthropometric data. Give alerts for wearing seat belts and used in safety tests for impact on a dummy in a car to improve airbags in cars.
5. Entertainment: Musical keyboards with pressure-sensitive keys, portable, pressure-sensitive drum kits and electric guitars. Lightorientated dartboard, dance mats linked to TVs and MP3 players in jackets.
6. Industrial: Military communication, high-vis jackets controlled by solar energy that allow the wearers to choose specific areas to make more visible. Pressure switches on tools and variable speed controls on drills. Also, sensors are used as safety features that cut the power on chainsaws when they’re not being held. Radiation sensors in both medical and industrial environments. Space and military suits used to manoeuvre robotic instruments, unmanned vehicles or remote devices.
Optical Fibers:
These fibers are made of glass or plastic, and they have high optical clarity. Light travels internally through the fiber across long distances via reflection, and it retains its luminescence. Signals can be passed in either analogue or digital forms within a machine or from one machine to another.
Properties:
- Light-Emitting in varying colours
- Brittle which is why such fibres are encased in steel wire
- Washable
Uses:
Safety products such as vests and road signs. Dresses (Hussein Chalayan fibre-optic dress), shirts and health monitors, for example heart beat, body temperature, children susceptible to S.I.D’s. Uses also include soft furnishings, such as curtains, bed headboards and cushions. Other uses include umbrellas and flexible screens to display graphics and text used on jackets, rucksacks etc.
Voltaic Panels:
These are strong, lightweight, aluminium solar panels that are placed on the outside of products, usually in a flexible, fabric sleeve so do not restrict the use of the product to the wearer. They can generate up to 10W of power. The Fuse 10W solar laptop charger can be attached to products such as backpacks and panniers via the flexible buckle and strap system and it can be used to charge a variety of products.
Properties:
- Scratch-Resistant
- Waterproof
- UV-Resistant
- Flexible
- Durable
Uses:
Charging mobile phones, iPods, cameras and torches.
References:
- Fibres to Fabrics by Bev Ashford
- High Performance Technical Textiles Edited by Roshan Paul
- https://www.loomia.com/blog/passive-vs-active-smart-textiles
- https://active-textiles.com/
