AIST Stories No2

8From AIST to the Innovative WorldEasy to mold and has high heat resistance but has low strength and breaks easily—— Claist flexible clay film overturned this image of clay. Developed by AIST, Claist is comprised of 1 nm (nanometer; n: 10–9) thick clay crystals; it has extremely high barrier properties for hydrogen and water vapor. It is already widely used as a sealant to prevent gas leakage in chemical plants. Moving forward, this clay film is expected to contribute to the realization of a safe, secure and moreover comfortable society through adoption in applications such as fuel cell vehicle hydrogen fuel tanks and OLED display substrates.The thinner the film, the greater the barrier properties?!Clay materials are weak in water and soft unless fired, but once fired, they become brittle and break easily. As such, they tend to present an image of exhibiting high plasticity*1 coupled with low strength. In fact, this fragility meant that it was difficult to form thin ceramic films. However, in 2004, AIST defied conventional wisdom by successfully fabricating a flexible film from ceramic that was as thin as paper. The gas barrier properties*2 and heat resistance of this film were found to be extremely high. The name for the film, Claist, was derived from the words “Clay” and “AIST.” Currently, applications and commercialization are advancing in various industrial sectors.AIST’s Research Center for Compact Chemical System is located in the east of the city of Sendai. Here, Prime Senior Researcher Takeo Ebina is the “father” of Claist. Ebina’s original specialty was waste treatment for environmental protection and he was researching methods to utilize clays as barrier materials for preventing leakage of organic Prime Senior Researcher, Team LeaderAdvanced Functional Materials Team, Research Center for Compact Chemical SystemTakeo EbinaA clay-based film with astounding gas barrier properties and heat resistanceVarious applications are being deployed, from chemical plants to packaging materialsClaist: a high-performance clay-based thin filmLeading the wayAIST!Our life and society will change in this way!