Safety film
From Wikipedia, the free encyclopedia
Photographic film called safety film is made with a film base of either acetate or polyester. Bases known as "acetate" are chemically either cellulose diacetate, cellulose acetate propiarate, cellulose acetate butyrate, or cellulose triacetate. Beginning in the 1920s, acetate replaced nitrocellulose (nitrate) film bases used previously as the film stock used in both amateur and professional applications. Polyester bases began to be developed in the 1940s.
Cellulose triacetate films are still in wide use today for applications such as original camera negatives, but polyester has largely replaced acetate in recent decades for usage in release prints and intermediates. This is due to polyester's qualities of higher stability and durability for archival and post-production purposes.
