yes, they work wonderfully. I am like you and prewash my fabric. I had made a quilt for my son, mostly whites and creams with dark blues and a very dark blue batik border. I prewashed the border with color catcherS and they came out almost navy blue! If this happens to you, WASH IT AGAIN! I must have missed a white or two and the blue still dumped dye on the white! It was not dark, and my son thought it was supposed to be that way, but I was upset. Use Synthropol, rewash till you are happy, but don't use it until you are! ( am sure you wont have this problem...but beware!)
I'm with homebody on this. I just made a jacket with batiks. It was supposed to be a bit 'flowy'...and its stiff. Are you sure you want batiks next to your face? How about just a bed runner with a nice soft flannel or minkee backing?