n.a flexible plastic made from cellulose, usually wood pulp or cotton, mixed with nitric and sulfuric acidsArbaugh 1939, 106Motion-picture film is of two kinds, cellulose nitrate and cellulose acetate. The first, commonly used for commercial motion pictures, is chemically unstable and very inflammable. The process of deterioration, once begun, proceeds at an accelerating rate and is accompanied by the formation of extremely poisonous gases which make the presence of such film doubly hazardous.Raney 1939, 145We shift from cellulose nitrate, despite its superior flexibility, over to cellulose acetate, and thus get out of the gas and gunpowder range, while preserving nimbleness by keeping an eye to humidity.Barrow 1943, 153His findings likewise stressed the fact which had been before stressed by the National Bureau of Standards that cellulose acetate is a far different product than cellulose nitrate which is unstable and injurious to paper.Calhoun 1967, 517Unfortunately, all early motion-picture films were made on a cellulose-nitrate base, which is chemically unstable and a serious fire hazard.Ritzenthaler 2010, 91Cellulose nitrate ¶ Formed by the reaction of cellulose with nitric and sulphuric acids. The first synthetic plastic; used extensively as a photographic film base as well as a consolidant and an adhesive. Also used as a coating, as with pyroxylin-coated book cloth. Unstable.Ritzenthaler 2010, 373Cellulose nitrate: An extruded plastic made from cellulose, usually from wood pulp or cotton, mixed with nitric and sulfuric acids. Cellulose nitrate was commonly used as the base of photographic and motion picture film from the late nineteenth century through the early twentieth century. It is highly flammable and unstable and exhibits distinctive stages of deterioration when stored under normal room conditions.Heckman 2010, 483Flammable, inflammable, and combustible, if ignited, nitrate—or cellulose nitrate, or nitrocellulose—film stock cannot be extinguished.Matusiak and Johnston 2014, 246Cellulose nitrate film was first used for roll films and later for sheet films in a variety of formats.NEDCC 2020b, 1In August 1889, Eastman Kodak began selling the first photographic negatives on cellulose nitrate flexible film support. This innovation was the foundation of an entirely new era in photography. The increased convenience of flexible films enabled professional photographers to take more photographs under a wider variety of conditions; it also created a new amateur market which quickly became the economic foundation of the photo industry. Nitrate film remained in production in various formats until the early 1950s.Joffrion and Cloonan 2020, 113Nitrate film, held by many archives, is unstable. Cellulose nitrate decomposition causes the film base to shrink and yellow. The base can become brittle and sticky, often leading to complete disintegration. Furthermore, elevated temperature and humidity levels will cause the film to deteriorate quickly. As the film breaks down, it gives off nitric acid and can self-ignite at temperatures around 100 degress F. Even more alarming, if the film is maintained in a tightly close container and the gases cannot escape, spontaneous combustion can occur.
Notes
Also known as nitrate and nitrocellulose, cellulose nitrate was commonly used as the base in photographic and motion picture film from the late-nineteenth century through the early-twentieth century. It is chemically unstable and highly flammable. In advance stages of deterioration it can combust spontaneously.
