It is inkjet, amazon have 10 sheets for £4.74 but you could probably find it cheaper with a quick search.
A4 OHP Inkjet Transparency Film Sheets 135 micron Instant Dry should get the desired result
Thanks, any particular make? I use Ernie Ball on my strat, 9's, at the moment I'm using medium wound on my Fender acoustic and, as you say, after a while my fingers ache and it isn't easy, not impossible, but not easy to do full bends, especially with my fourth finger.