Light responsive textiles provide a response to a light stimulus, light is defined by its wave length and frequency as part of the Electromagnetic Spectrum.
Textiles which encounter and react to stimuli are termed SMART Textiles. They are categorised based on the reaction;
- Photochromic- light induced colour changing
- Photoconduction- light affects electrical conductivity
- Photovoltaic- light produces an electrical current
With the term photoreactive meaning reacting to light.
This ability to react to a light stimulus, which is usually in the UV light region, has gained a variety of applications across textiles and apparel. Photochromic effects have gained popularity in novel applications in apparel, such as in clothing that displays a different colour, or applied in a print/pattern which is only exposed in the sunlight. From this application the technology was more finely tuned to act as an indicator of when too much sun (or UV) exposure has occurred, and this applied to clothing and accessories as a safety indicator, gaining particular attention for children’s wear. This same technology has been applied as an anti counterfeiting measure.
Colour change materials are sometimes referred to as chameleon materials, which look at biomimicing the chameleon’s skins to provide reversible colour changes. (Click here for more information)
More information on Chameleonic Textiles is available in the Innovation tab.
In Interiors textiles used as window dressings have been engineered to react to UV exposure and turn opaque or translucent to prevent sun glare.
Harnessing the sun’s energy and converting it into electricity is already a reality through the use of solar panels. However if this same technology can be incorporated into textile it would revolutionise our interaction with current electrical technologies and open up the possibilities for smart or electronic textiles. If textile materials were the power cell for some of the technologies we use on a daily basis, such as our mobile phones or satellite navigation, reducing the weight and bulk of batteries and offering a green and sustainable energy source for the future. Not only in apparel applications but amongst a wide range of technical textile applications, such as roof felting, geotextiles, interior textiles such as window dressings, or in automotive. Even if textiles could only harness a small percentage of the suns energy, because of their large surface area, this small percentage may equate to a substantial amount. It is because of this huge potential to revolutionise that there has been a great deal of interest in the integration of photovoltaic materials into textiles.
A new area of light responsive textiles is emerging for wellbeing. This focuses on the impregnation of textiles, either at the yarn production or fabric finishing stage to embed mineral particles at the micro or nano level. The effect of these particles is that they harness the electromagnetic emissions from the human body and convert them to a level which has a positive affect on the human body by increasing circulation and thus oxygen flow. There has been an emergence of products which claim to possess these qualities; more information is in the Innovations tab.