How about paper paint in a spray can. Every time I go to the post office to mail a box I'm given the third degree and a large, smelly, black magic marker to cross out the words like liquid, cleaner, electric. I haven't time to go buy a box so if I invented a spray that was brown paper bag in a spray can? Like a correction film on a bigger scale? What could the postal-postal worker say then?
(actually don't want to know) would probably reject the box due to potential flammablity, but our lab could work on that.
