My fault. I thought they use the approach described in [1], where the prototype used LightScribe DVD optical drive to make a pattern on a disk with graphite oxi

My fault. I thought they use the approach described in [1], where the prototype used LightScribe DVD optical drive to make a pattern on a disk with graphite oxide film. That prototype didn't require any liquid. [1] http://www.sciencemag.org/content/335/6074/1326 http://www.sciencemag.org/content/335/6074/1326