I don't know what it's called because I haven't used it, but there is supposedly some kind of sheet tht you put in the washer, and it collects all that color. I don't remember where I read it (either in this quilt group or one of two others that I'm in), but the person that uses it puts a few sheets in at a time, and has never had a problem with colors bleeding. I wonder if that would work for it. Worth a try. I iwll see if I can find that post. I just saw it not even a week ago.
EDITED TO ADD: Shout Color Catchers:
http://www.shoutitout.com/preserve-colors.aspx