I had a red backing fabric not just bleed but RUN JOYFULLY through the bathwater on an antique quilt top. I had figured a few color catchers and the red would be fine like it always has. As soon as the quilt hit water the red plumed through the water as my heart fell. I did everything in cold water, four different soaks, spin outs, etc.. I finally tried the hot water and Dawn. It's amazing how beautiful the quilt came out. There was a touch of pink in a couple of spots that were there from the first soak. They became much lighter when I followed the "scary" directions of hot water.