Japanese company is developing a cloth into which optical fibers are woven.
Toyota Boshoku Corp succeeded in weaving two layers of optical fibers by improving manufacturing technologies, enabling to show more complicated patterns than before. By using multiple colors, it becomes possible to show vivid patterns.
Toyota Boshoku expects that the cloth will be applied to automotive interior parts such as door trims and roofs. The company aims to commercialize it in early 2020s, aiming to supply it to Europe-based luxury car makers and Toyota Motor Corp’s “Lexus.”
The cloth has a curved form with two layers woven. By making it possible to form a shape in accordance with the shapes of auto interior parts, the cloth is now one step closer to volume production.
“Especially, luxury car makers are becoming more particular about interiors year by year,” Toyota Boshoku said.
The company plans to promote the cloth by improving its functions.
As light sources, the cloth uses RGB (red, green and blue) LEDs, and it is possible to change colors in accordance with the taste of passenger. For example, it is possible to emit green light from the door trim and roof at normal times and emit red light at the time of applying an automatic brake in an emergency. Toyota Boshoku considers that the cloth can contribute to improving not only comfort but also safety.
Optical fibers used as weft
The cloth is formed by weaving warp and weft, and Toyota Boshoku replaced part of the weft with optical fibers. The company developed a dedicated machine for weaving optical fibers while keeping their almost linear shape. And the company is improving manufacturing technologies in cooperation with an affiliated company.
The optical fibers are made of acrylic resin, and their diameter is about 0.25mm. The fiber part called core layer has a diameter of 0.24mm, and it is covered with a 0.005mm-thick fluorine layer.
When the bending rate of optical fiber is increased too much, it becomes difficult for light to pass through the inside, making light emission unstable. Therefore, optical fibers cannot be easily applied to significantly curved interior parts.
Durability is also one of the cloth’s problems. And Toyota Boshoku considers it difficult to apply the cloth to auto seats.