You can make it at one of the Artisan Material Something People, if my memory serves me right, the person near Dunes of Despair..? He also crafts Deldrimor Steel, Bolts of Damask, Charcoal (for only 5 wood and some gold, or something) and lots of other rare materials.
My guess is that is may be used to craft scrolls (those crazy single-use things that increase the EXP income of a whole party for a duration of time, or some other crazy boosters).
The crafters who make the ink and glass vials are more like second tier crafters. The ones who make deldrimor steel, damask, vellum, etc only make materials that are needed for ascended armors.