Coincendentally, We've Recently, somewhat researched (RIT DYE)
It seems there are not only (Liquid and Powde), but you'll need to be even more observant , As weve found there are also All Purpose and Synthitic, in at least the Liquid form. and as it seems array of color are abit hard to find.
Sheilajeanne's link to a color chart is the only place we 've found for different colors. Hope this furthers your inquaries !