There really aren’t a lot of full-colour 3D printers on the market. Why is that?
The original 3D printing process from years ago, FDM, SLA, and SLS, while very different, had one thing in common: they used only a single material. As a result, for many years, all 3D printed parts were a single material and colour.
Some FFF machines were adapted to have more than one printhead, enabling two or sometimes three colours in a single print job, but that isn’t really full colour. Full-colour 3D printing would enable coverage of the entire colour spectrum, including gradients and complex textures.
Two early attempts at full-colour 3D printing included the Z-Corp process, which was a binder jet approach. A bed of white polymer powder was printed layer by layer using an inkjet head. The ink was the binder — and the colour. It’s as if you were printing a full-colour “page” on each layer. After many layers, you’d get a washed-out full-colour print.
Another approach was attempted by MCOR Technologies, which used a plain paper approach. They’d glue layers of paper together, cutting each layer at the object’s perimeter. After the job completed, you’d pull out the cut-offs to reveal the object.
Later, they added an inkjet function to print colours on the edges of these cuts, which would become the outside of the object when done. This also produced full-colour prints, but they were also somewhat washed out.
Neither process produced realistic colours.
Today, we have basically two vendors providing realistic full-colour systems: Stratasys’ J850 and Mimaki. Both use a similar process involving resin and UV curing and can produce objects that are highly realistic in appearance — until you pick them up.
These two options really do work if you want to print truly full-colour objects.
So why aren’t we seeing a lot of this these days?
While the original full-color processes failed because they could not properly reproduce full colours, today’s options still have a couple of other barriers to overcome.
One is that there simply isn’t a big demand for colour objects. Most printed parts are functional or don’t require full colour textures. Because the full colour parts are mechanically different from actual products, they can’t often be used as end-use items. Instead, they are usually relegated to testing the appearance of products, which is far lower volume than the products themselves.
The second and more daunting barrier is price. The cost of full colour 3D printing is still quite high, requiring six-digit purchases of equipment, with pricey materials to follow. Until someone invents a full colour process that is more economical, that’s what we’re stuck with.
For the foreseeable future, most 3D printer operators likely won’t have access to true full colour 3D printing.
