As a good electronic hobbiest tradition I started to design a businesscard from PCB material. Downside of all the businesscards (and PCBs in general) is the limited number of colors you can use: FR4, soldermask (with or without copper behind it), silkscreen or bare copper. Since the soldermask is fixed for both sides that was an extra limiting factor.
An out of the box solution I found was decal slide paper. This is a printable plastic film that is used to decorate ceramics or glass. There are clear and white versions and they can be found in most hobby stores. They are easily printed on by an inktjet or laser printer and have thus an infinite range of colors. For this experiment I bought clear film and designed the PCB with black soldermask (needed that color for the front side) and white silkscreen.
The print is applied by submerging it into water and wait a bit. After a while the decal lets loose and can be careful applied to the pcb (also submerged). It is a bit trickery as the film is very thin and is easily crinkled. When it is positioned right it needs to dry for 24 hours. After this time I backed it in the oven for 10 minutes at 120 degree Celsius. Optional a layer of clear coating can be applied to make it more durable.
As I found out the decalfilm is not very fond of acetone, so clean the board before applying the decal 🙂 Also the use of lots of dark colors makes it less stick to the decalfilm (the white spots in the foto).