Yes you can cover your sensor in any other non-conductive material, eg, other paint, plastic, glass, wood. You sensors can work through a table for example or through a glass window.
Depending on the thickness of the material you may need to calibrate the sensitivity of your sensors, by adjusting the code on the Touch Board.
Some good tutorials that can help with this are:
Also Checkout or other FAQ about using another paint as an insulator: