that’s easy, 1st, you have to drench the shirt in lighter fluid 2nd, you take a lighter or matches whatever you prefer; then light the shirt on fire.that’s it!! You’ve removed the screen from the shirt.P.S: you might wanna keep a fire extinguisher handy.
on a serious note, the big player in chemicals for screen printing is sericol. Their products are available from a number of outlets. Try eBay or the following websites.
NAIL POLISH REMOVER FOR VERY SMALL AREAS WORKS ALRIGHT
http://www.fujifilmsericol.com/GraphicScreen/InksApplications.htm
http://www.birthdaypartyheliumballoondelivery.co.UK/Birmingham/balloon-archive/99-balloon-printing