Synthrapol will not STOP a bleed. It is designed to keep the dye particles from adhering to other fabrics. If you want to wash a quilt and are worried that some of the fabrics might bleed into other fabrics in the quilt, use Synthrapol. I have had very good luck with Retayne when used according to directions. However, you also need to consider the quilt usage, how often it will be washed and who will be washing it. I don't think I have ever washed a quilt in hot water--dry on hot in the dryer--but not hot water wash. Have you?