Procion MX
  • I am going to dye undyed rayon yarn using Procion MX. Do I pre-treat the yarn by wetting it first? After dying it, do I rise it in cold water until the water runs clear?
  • At the very least you'll need soda ash to make a solution for wetting the yarn first. You might be able to just add soda ash solution to the dye to start it reacting and dye the yarn dry, but you'd have a limited time to use the dye before it would all have reacted with the soda ash.

    I'll definitely be checking back here to see what other responses you get, though, as yarn is one thing I have not yet tried dyeing. :-)