
Black and white film is long lasting and more permanent than color film. The first flexible films, dating to 1889, were made of cellulose nitrate, which is chemically similar to guncotton. A nitrate-based film will deteriorate over time, releasing oxidants and acidic gasses. It is also highly flammable. Special storage for this film is required. It is highly explosive and should be kept at low temperatures, in sealed bags, in fireproof vaults.