Safety film
Photographic film called
safety film is made with an acetate base, chemically either cellulose diacetate, cellulose acetate propiarate, cellulose acetate butyrate, or cellulose triacetate. Beginning in the
1920s, it replaced
nitrocellulose, or
nitrate, film bases used previously.
Cellulose triacetate films are still in use today for some applications, but have largely been replaced with polyester bases that are more stable and more durable.