Most plastics are inherently insulating, which causes charge to build up on their surfaces. A common approach to increase plastic conductivity is to blend in conductive fillers. However, these fillers reduce mechanical strength of the plastics, change their color, and make processing more difficult. A solution to these problems is Invisicon® as an anti-static coating.
Invisicon can function as an anti-static or ESD coating with a surface resistance between 103 -1010 Ω/□. These coatings cover a conductivity range suitable for dust control, charge bleeding, and electrostatic painting. Invisicon® is a sufficiently thin coating to not alter the mechanical properties of a part, and will not affect the transparency or color of the substrate. Invisicon® can be applied to a finished part, so it also does not require retooling molds or presses. Plastic sheet stock can also be coated with Invisicon® and then further molded while still retaining conductivity.
Takiron Inc of Japan produces ESD transparent conductive plastics under license from Eikos. Eikos non-exclusively licensed the technology to Takiron LTD in 2004. For more information see our press release.
Invisicon® ESD coatings have demonstrated their performance and durability in the harshest environment: outer space. In 2001, Eikos sent several carbon nanotube-binder composite coatings into space to learn how low earth orbit affects the critical properties of transparency and conductivity for static dissipative applications. These coatings used a binder designed for space stability to protect the coatings’ electronic properties. These samples were part of the NASA MISSE program and spent four years outside of the International Space Station.
Samples were exposed for four years in low earth orbit to:
- atomic oxygen
- vacuum ultraviolet
- thermal cycles of a hundred degrees
...and still retained their conductivity, transparency and mechanical integrity.
For more information on MISSE, please visit http://misseone.larc.nasa.gov
Eikos is continuing to develop Invisicon® for space and aerospace applications, specifically:
ESD control of solar arrays
Eikos is working with USAF AFRL at Kirkland AFB to integrate Invisicon® in the form of an anti-reflective nanotube composite film that dissipates charge and increases performance of the solar array. These coating are radiation hard, thermally stable, with high adhesion, and are useful on glass, organic and inorganic polymers. (see News)
ESD control on aircraft canopies and windscreens
The invention of Invisicon originates with USAF support back in late 1990 under the SBIR program with the solicitation of new transparent conductive coatings for use on aircraft transparencies. Since those early years this application has expanded and recently Eikos has reengaged with the USAF to exploit Invisicon® technology in new ways and push performance levels. (see News)
Eikos has many other product development efforts underway to exploit Invisicon Technology for ESD and AR coating in commercial applications.