Be careful you don't wreck your printer!
I'd suggest printing onto thin(ish) paper and then sticking to the plasticard and varnishing them (1st coat gloss, 2nd matt).
It is similar to what I do to make really detailed 15mm and 28mm flags (especially if there is heraldry to be painted).
I print out the design onto as thin printer paper as I can get hold of. Then I stick it to thick foil (Sainsbury's tomatoe puree tubes are fantastic ... we eat a lot of tomatoe based sauces in the Fry household ... pure coincidence
). Then I bend the flag into shape and piant it up.
Obviously the foil idea wouldnt work for terrain ... but you get the idea.