I just got done "testing/washing" over 200 pieces of batik. I have been buying them for over a year when I found a pattern that called for 30 fat quarters - Lucky Stars. I just loved them so much that I kept buying but decided to buy 1/2 yard pieces instead of the fat quarters - more, if I found a bargain on batiks somewhere (not very often though). I finally decided that I had enough and started washing them in a pure white kitchen dishpan. OH MY, about 1/2 of them bled and actually wound up throwing two of them away because they never did stop bleeding. I put lukewarm water in my dishpan along with a few drops of detergent and squeezed my pieces around a few times to see if they bled. If they did not, then I rinsed in cool water, wrung out very gently and rolled up in fluffy towels - then put them on an indoor clothesline to dry. Not too much wrinkling that way. Some, I had to rinse many times until the water was clear.
HTH