Page "Film stock" Paragraph 23

A piece of film consists of a light-sensitive emulsion applied to a tough, transparent base, sometimes attached to anti-halation backing or " rem-jet " layer ( now only on camera films ).

Originally the highly flammable cellulose nitrate was used.

In the 1930s, film manufacturers introduced " safety film " with a cellulose triacetate plastic base.

All amateur film stocks were safety film, but the use of nitrate persisted for professional releases.

Kodak discontinued the manufacture of nitrate base in 1951, and the industry transitioned entirely to safety film in 1951 in the United States and by 1955 internationally.

Since the late 1990s, almost all release prints have used polyester film stock.