I found a great blog posting on CreativeTheHive.com on how to sun print with ordinary fabric paints mixed 50/50 with water. Very interesting. Check out the following blog for clear descriptions and photographs of the process.
Fun in the Sun Printing http://t.co/YTPmvu9 via @creatingthehive
I haven't tried this yet, but will test it out tomorrow and post a follow-up, hopefully with pictures to show the outcome