It almost certainly uses black ink. All parts produced with the machine they have now are to be black. It technically doesn't use beads, it uses plastic powder. It works exactly as you described though.
Oh, yeah. I put the UV part in there because of the talk about full color printing. The first time through that video I missed the key phrase "could in the future"[1].
Well, I'd assume white counts as a color, as well as other light colors. Plus they then go on to talk about printing clear things. You need to absorb energy from somewhere so I figured UV was about all that was left.
