Here’s the result of my wash-out test. Everything had a cold rinse, and some were hung to dry. When all the fabric was dyed and rinsed, we filled the washing machine with the hottest water available, added Metaphos (water softener) and Synthrapol. Once it was full and had started agitating, we added the fabric. I ran the washer extra long – 25 minutes, then let it finish its cycle and dried. No backstaining -yay!