Thanks Chris and Umut. Looks interesting. Does anyone have access to the full article? There are also some patents that refer to the same sort of idea. Would it be likely to work with sodium hydroxide as well? The first page mentions polycarbonate as well as PET. I've got a whole roll of polycarbonate film to experiment with. I'd figured out a way to sub it but it didn't come out looking very nice and wasn't as flexible as when I started.

Then again, I haven't made much of a dent in the support Denise sent me. :-(