If you had yardage doing that, I'd recommend Retayne. For scraps, I'm with CheshireCatQuilter -- toss them. If you really, really love them -- I might try sending them through the wash on cold water, gentle cycle or hand wash, with a small amount of regular detergent, block & let air dry (so you don't have to iron them again). If that works, great. If not -- it's probably not worth all the expense to buy a fixative. To check if it worked, when totally dried rub a white cloth on the fabric. No dye should come out.