Seiichi Takamatsu / Associate Professor / Division of Environmental Studies
Department of Human and Engineered Environment Studies / / Wearable Devices, Flexible MicroElectroMechanical Systems (MEMS), E-Textile

Career Summary
2003: Graduated from the Faculty of Engineering (University of Tokyo)
2009: Received Ph.D. in Information Science and Technology from the University of Tokyo
2009: Technical Staff, Postdoctoral Fellow, AIST
2010: Researcher, BEANS Laboratory
2012: Researcher, AIST
2016: Associate Professor (University of Tokyo)

Educational Activities
Undergraduate: English Presentation

Research Activities
Wearable electronic textiles (2009-present): Wearable devices are receiving a great deal of attention as they have the potential to become a key technological tool for information technologies and healthcare. In order for this potential to come to fruition, we developed a new fabrication technique to form a precise electrode and electroactive pattern on knit textile. We utilized polydimethylsiloxane (PDMS) as the stencil due to its hydrophobic nature, which can confine the aqueous conductive polymer solution of PEDOT:PSS. Electrode was formed on the knit as a wearable keyboard [1]. The biomedical electrode is also fabricated for recording high quality electrocardiograms [2].

Wearable Keyboard

Meter-scale large area electronic textiles (2009-present): Meter-scale large area electronic devices are optimal for smart home applications such as floor sensors and energy saving lights. We developed a fabrication process that consists of reel-to-reel chip mounting on ribbon with copper wires and automatic weaving of ribbon. LED-embedded sportswear and a tent have been fabricated with our process [3].

Fabrication process of meter-scale electronic textile devices and LED-embedded tent

1) S. Takamatsu, T. Lonjaret, E. Ismailova, A. Masuda, T. Itoh, and G. G. Malliaras, "Wearable Keyboard Using Conducting Polymer Electrodes on Textiles," Advanced Materials, published online DOI :10.1002/adma.201504249, Dec. 2015.
2) S. Takamatsu, T. Lonjaret, D. Crisp, J. M. Badier, G. G. Malliaras, and E. Ismailova, "Direct patterning of organic conductors on knitted textiles for long-term electrocardiography," Scientific Reports, vol. 5, 15003 (7 pp.), Oct. 2015.
3) S. Takamatsu, T. Yamashita, and T. Itoh, "Meter-scale large area LED-embedded light fabric for the application of fabric ceilings in rooms," Microsystem Technologies-Micro-and Nanosystems-Information Storage and Processing Systems, vol. 21, pp. 1209-1217, Jun. 2015.

Other Activities
Institute of Electrical Engineers of Japan (IEEJ)
The Japan Institute of Electronics Packaging (JIEP)
Institute of Electronics, Information and Communication Engineers of Japan (IEICE)

Future Plan
The conventional fabrication process of wearable devices requires high temperature heating and chemical treatment, which deform the textile substrate. We are developing a new fabrication process for wearable and large area electronic textiles.

Messages to Students
Collaborative research is essential for high impact scientific study. Therefore, our laboratory strongly promotes students to work with industrial and international collaborators. This will help you become a researcher that makes innovation happen.