celluloid

Celluloids are a class of materials produced by mixing nitrocellulose and camphor, often with added dyes and other agents. Once much more common for its use as photographic film before the advent of safer methods, celluloid's common present-day uses are for manufacturing table tennis balls, musical instruments, combs, office equipment, fountain pen bodies, and guitar picks.

==History== thumb|upright|Celluloid and sterling silver pen. ===Nitrocellulose=== Nitrocellulose-based plastics slightly predate celluloid. Collodion, invented in 1846 and used as a wound dressing and an emulsion for photographic plates, is dried to a celluloid like film.