Foldable and washable textile-based OLEDs with a multi-functional near-room-temperature encapsulation layer for smart e-textiles

So Yeong Jeong,Kyung Cheol Choi,Ki Suk Kang,Yong Cheon Park,Ha-Eun Cho,Hye Rin Shim,Yongmin Jeon,Yunha Na,Junwoo Lee,Eun Gyo Jeong,Sung Gap Im,Jeong Hyun Kwon,Seungyeop Choi

doi:10.1038/s41528-021-00112-0

Abstract

Wearable electronic devices are being developed because of their wide potential applications and user convenience. Among them, wearable organic light emitting diodes (OLEDs) play an important role in visualizing the data signal processed in wearable electronics to humans. In this study, textile-based OLEDs were fabricated and their practical utility was demonstrated. The textile-based OLEDs exhibited a stable operating lifetime under ambient conditions, enough mechanical durability to endure the deformation by the movement of humans, and washability for maintaining its optoelectronic properties even in water condition such as rain, sweat, or washing. In this study, the main technology used to realize this textile-based OLED was multi-functional near-room-temperature encapsulation. The outstanding impermeability of TiO2 film deposited at near-room-temperature was demonstrated. The internal residual stress in the encapsulation layer was controlled, and the device was capped by highly cross-linked hydrophobic polymer film, providing a highly impermeable, mechanically flexible, and waterproof encapsulation.

Highlights

With the emergence of the Internet of Things (IoT), the value of connecting humans and smart electronic devices is increasing
Wearable display devices are interface devices that lead the hyperconnectivity between humans and wearable electronics by visualizing the information processed in wearable electronics to humans
By utilizing this multi-functional encapsulation on both the top and bottom sides of the organic light emitting diodes (OLEDs), a real wearable OLED was realized on conventional dress-shirts and T-shirts

Summary

Introduction

With the emergence of the Internet of Things (IoT), the value of connecting humans and smart electronic devices is increasing. To realize a reliable, foldable, and washable textilebased OLED, a multi-functional encapsulation that simultaneously exhibits an WVTR on the order of 10−6 g m−2 day−1, high transparency, high curvature flexibility, waterproof property, and a near-room-temperature process was developed.

Results

Conclusion