Nitrate film being stored in a 20th Century Fox facility spontaneously combusted, destroying more than 40,000 reels of negatives and film prints.

Nitrocellulose is a highly flammable compound formed by nitrating cellulose through exposure to a mixture of nitric acid and sulfuric acid. One of its first major uses was as guncotton, a replacement for gunpowder as propellant in firearms. It was also used to replace gunpowder as a low-order explosive in mining and other applications. In the form of collodion, it was also a critical component in an early photographic emulsion, the use of which revolutionized photography in the 1860s. In the 20th century, it was adapted to automobile lacquer and adhesives.

20th Century Studios, Inc., formerly 20th Century Fox, is an American film production and distribution company owned by the Walt Disney Studios, the film studios division of the Disney Entertainment business segment of the Walt Disney Company. It is headquartered at the Fox Studio Lot in the Century City area of Los Angeles, which is leased from Fox Corporation. Walt Disney Studios Motion Pictures distributes and markets the films produced by this studio in theatrical markets.

A major fire occurred in a 20th Century-Fox film-storage facility in Little Ferry, New Jersey, United States on July 9, 1937. Flammable nitrate film had previously contributed to several fires in film-industry laboratories, studios and vaults, although the precise causes were often unknown. In Little Ferry, gases produced by decaying film, combined with high temperatures and inadequate ventilation, resulted in spontaneous combustion.

In photography, a negative is an image, usually on a strip or sheet of transparent plastic film, in which the lightest areas of the photographed subject appear darkest and the darkest areas appear lightest. This reversed order occurs because the extremely light-sensitive chemicals a camera film must use to capture an image quickly enough for ordinary picture-taking are darkened, rather than bleached, by exposure to light and subsequent photographic processing.