Nitrocellulose (also: cellulose nitrate, flash paper, flash cotton, guncotton, flash string) is a highly flammable compound formed by nitrating cellulose through exposure to nitric acid or another powerful nitrating agent. When used as a propellant or low-order explosive, it was originally known as guncotton. Partially nitrated cellulose has found uses as a plastic film and in inks and wood coatings. (source)