スカーフで情報伝達？　中国の研究者ら、発光繊維のスマート生地を開発

【東京ＡＦＰ＝時事】一見これといった特徴はない、織り目の粗いスカーフのようなこの生地は、情報を伝えることができる。身に着けたり、畳んだり、洗ったりできる上、ディスプレーとして完全に機能する。メッセージや画像を素早く表示するだけでなく、キーボードを組み合わせた使用も可能だ。（写真は中国・上海の復旦大学の彭慧勝教授チームが開発した生地）
　中国・上海にある復旦大学高分子エンジニアリング学部の彭慧勝教授が率いるチームは１０日、英科学誌ネイチャーに「ディスプレー・テキスタイル」の研究成果を発表した。
　ウエアラブル電子機器の進歩は著しく、すでに超薄型ディスプレーなどの機能を搭載した衣類が登場している。しかしそうした製品は、薄いフィルム状の発光素子を布地に貼ったり織り込んだりして作られているため、通気性や柔軟性に乏しい、壊れやすいといった問題があり、また決められたパターンしか表示できないことが多い。
　彭教授のチームは約１０年間にわたる試行錯誤の末、織布の縦糸と横糸が交わる箇所に、極小の光の点を作り出すことにした。
　このような極小の光の点を作るには、木綿などの繊維と一緒に織ることが可能な発光性の縦糸と導電性の横糸が必要だった。そこでさまざまな組み合わせをテストし、発光物質でコーティングした銀めっき繊維の縦糸と、ゲルの一種から紡いだ導電性の横糸にたどり着いた。
　二つの素材は木綿と一緒に織り込まれ、長さ６メートル、幅２５センチの生地ができた。電流を加えると、銀めっき繊維の層と導電性ゲル繊維の接触部分が発光する。【翻訳編集ＡＦＰＢＢＮｅｗｓ】
〔ＡＦＰ＝時事〕（2021/03/16-14:05）

At first glance, the fabric looks like a pretty if not especially original scarf, with turquoise, blue and orange stripes in an open weave. But this fabric can communicate.
It's wearable, foldable and washable, but it's also a fully functioning display -- capable of flashing messages or images, or even being used with a keyboard.
The fabric, described in a study in the journal Nature on Wednesday, is the work of a team led by Huisheng Peng, a professor in the department of macromolecular engineering at Shanghai's Fudan University.
He believes it could revolutionise communication and help individuals with voice, speech or language difficulties to express themselves to others.
We hope that woven-fibre materials will shape next-generation electronics by changing the way we interact with electronic devices, he told AFP.
Wearable electronics have advanced significantly in recent years, and clothing incorporating electronic functions including super-thin displays is already available.
Another study published this week, for example, describes a wearable microgrid powered by the sweat of the wearer.
But there are limitations to most existing products.
They are often made by attaching or weaving thin film light-emitting devices to fabrics, resulting in a material that is not breathable or very flexible.
They are also often fragile and prone to damage, and in the past were only able to display pre-determined patterns.
- Warp and weft -
Peng and his colleagues have spent a decade thinking about ways to improve existing technology, experimenting with different materials.
One option they formulated did not display well in the dark, while another fibre they came up with did not perform when it was woven.
The breakthrough came after examining the structure of textiles and the way threads intersect with each other in the warp and weft of a woven piece.
The team decided to try to create minuscule points of light where the fibres of a woven cloth meet.
To make these tiny dots of light, they needed a luminescent warp and a conductive weft that could be woven together with cotton or similar fibres.
After testing different combinations, they settled on a silver-plated yarn warp coated with luminescent composite, and a conductive weft spun from a kind of gel.
The two materials were woven with cotton into a piece of fabric six metres long and 25 centimetres wide.
Applying an electrical current caused the layer on the silver-plated yarn to light up where it was in contact with the conductive gel fibre.
The amount of power needed to light up the display material was limited, producing no significant heating, the authors say, and the fabric survived a number of stress tests.
It was left in the open air for a month, put through 100 wash-and-dry cycles and folded 10,000 times, all without losing brightness.
- Overcoming language barriers -
The study says the fabric can be powered with batteries or even use solar energy.
But what purpose might it serve?
Peng sees a variety of options, including a dynamic sleeve display that could, for example, allow a driver to view a GPS map on their arm as they move around.
But he is hopeful the material could also help people overcome difficulty communicating because of health problems or language barriers.
In one experiment with the fabric, they collected brainwaves from volunteers who had either been playing a race car game or meditating -- simulating a person in a stressed or relaxed state.
When paired with a processor, the waves could then be translated into messages displayed on the fabric reading either relaxed or anxious.
Peng said there were several improvements to the fabric the team would now work on, including making the display brighter, the resolution clearer, and the luminescent points available in more colours.