Originally Posted by Lori S

Syntropol can be effective in removing the excess dye, but not always a final cure to a serious bleeding problem. Retayne is a better choice for setting the un set dye. But do note once treated with Retayne only wash in cold water or you risk the removal of the Retayne and the fabrics will bleed again. I have used both products prior to cutting on hand dyed fabric . I found that some hand dyes the sythropol removed so much the fabric was dull in appearance, but with Retayne I had more color retention.
Yes it is much better to deal with a bleeder/runner prior to cutting or construction as once cut or assembled there are fewer options.