Synthrapol is used for hand dyed fabrics to remove sizing in fabrics and to remove excess dyes for even dye results, but it does not set the dyes. You need to use Retayne and wash in very hot water. The Retayne suspends the dyes and they are removed with the water when spun out, then the rinse and drying process sets the dye remaining. When using Syntrapol on future washings you can only use warm water, not hot. Retayne, on the other hand, makes it so you can use hot to cold water to wash. When you don't know how the quilt will be cared for it is best to use Retayne, then the receiver can wash however they want.
These two products get confused and if you are not a fabric dyer it is hard to keep them straight. There is a website you can read more information by just searching for either product name.
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