To prevent staining from dye bleeds when I don't prewash fabric, I make sure the first washing of a quilt is done in a washing machine that uses ***lots*** of hot water and wash with Synthrapol. Front-loading domestic washing machines do not use enough water to dilute dye bleeds, so I go to the local laundromat. For a large quilt, I use their largest front-loading washer. Synthrapol helps loose dye particles remain suspended in water so they are rinsed away instead of settling into fabrics where you don't want them.