Celluloid

Celluloid refers to a family of plastic materials based on nitrocellulose dissolved and compounded with a plasticizer, commonly camphor. Developed in the mid-19th century, it was among the first commercially successful forms of plastic. The term was associated with early plastic goods such as combs, buttons, and photographic films, and was popularized as a general label for these products. The name celluloid was coined by John Wesley Hyatt, who in the 1860s–1870s refined a nitrocellulose-based material for commercial use, creating a transparent, workable plastic that could be molded and extruded.

In motion pictures, "celluloid" became a familiar shorthand for the nitrocellulose-based film stock used from the late 19th century into the mid-20th century. The base material was highly flammable and prone to decomposition, creating significant fire hazards. Beginning in the 1930s and 1940s, and more fully in the 1950s, the film industry transitioned to safety films—primarily cellulose acetate and later polyester—while nitrate-based stock persisted in archival storage, requiring specialized handling. The term "celluloid" thus remains a historical reference to early film stock rather than a modern material.

Beyond film, celluloid was widely used for photographic films, illustrations, and consumer goods before being largely supplanted by more stable plastics. Nitrocellulose formulations degrade over time, releasing acidic substances that can damage artifacts and require careful conservation.