Active Parylene-encapsulated Droplets for Displays


Poly(p-xylylene)s (Parylene) have been widely used in coating electronics and medical devices. The chemical vapor deposition (CVD) of Parylene is performed under low-pressure condition. Due to this low-pressure nature, liquids are generally thought to be inappropriate to use as deposition targets. However, we have successfully performed low-pressure CVD of Parylene onto the surface of low-vapor-pressure liquids such as silicone oil, liquid paraffin and glycerin. The process enabled the direct encapsulation of liquid droplets by very thin Parylene films to form electrically drivable structures. The arrays of such droplets of colored-liquids can be used as color pixel matrixes in a new type of display. By applying voltages, we were able to modify the distribution of colored-liquid inside such encapsulated droplets and change their color contrast. The area covered by colored-liquid inside a 1-mm-in-diameter droplet was shrunk to 30% with 200V applied voltage within 1/15 second.

References :
Nguyen Binh-Khiem, Kiyoshi Matsumoto, Isao Shimoyama, “Active Parylene-encapsulated droplets for displays,” American Chemical Society 235th National Meeting, New Orleans, USA, 2008.