We've been here before - full colour plastic 3D printing in desktop size. Two 3D Systems products that promised just that, never saw the light of day; several Kickstarter projects have claimed just that, but not delivered.
We've had machines that dye the filament before extrusion, machines that mix the filaments during extrusion and ideas of ones that spray the print after extrusion. But the truth of the matter is, if you want a full colour plastic 3D print, go big or go home.
One company making a real go of the world of full colour 3D printing is Taiwanese outfit, ComeTrue. 3D Printing Tokyo offered me a first chance to get a good look at the tech.
Although it was not operating what I did see is a well-built bit of kit that had some pretty nice examples sitting beside it.
It uses the same principles as 3D Systems' ZCorp tech - to a plaster gypsum based powder a binding solution is applied, making the part solid, each layer is then sprayed with a CMYK colourant to achieve a photo realistic colour effect.