Celluloid is the trade name of a series of plastic materials, invented between 1863 and 1868 (the right period is not known) by John Wesley Hyatt, obtained from dinitrocellulose (nitrocellulose at 10-11% nitrogen) plasticized with camphor.
Celluloid is a very flexible material (made so by the plasticizing action of camphor) and resistant to moisture. However, the celluloid is also extremely flammable (due to the presence of nitro groups in the nitrocellulose), and this limited the possibility of use.
Diffusion and applications
The spread and relative applications of celluloid are to be considered as successful attempts to find a use for this material, which led to major revolutions and innovations in various fields. The celluloid, therefore, can be considered as the progenitor of some technological developments, still used today.
In 1887, for example, a Protestant shepherd patented its use as a support for photographic films. Since then, there has been a revolution in the field of photography that led to the birth of cinema.
In 1909, however, a French chemist accidentally discovered its possible use as a support to prevent the dispersion of glass splinters, following accidental breakage. Even in this case, this discovery led to the creation of laminated glass (safety glass), initially designed for the automotive industry, but whose first use, unfortunately, was in the production of glasses for gas masks, during the Great War. Given the excellent response in terms of material properties, celluloid was used a second time for similar applications, but this time during the Second World War.
Again, in 1938 celluloid was used by a German engineer as a communication interface for the first programmable computer in history, highlighting excellent responses in this field of application.
The main limit of celluloid: flammability
However, from 1954 celluloid lost its importance and ceased to be used for the production of photographic and cinematographic films, precisely because of its high flammability. This decision was taken in a future vision of greater security towards society.
This material was initially replaced by cellulose triacetate (artificial polymer), then the latter was in turn abandoned to be replaced by polyethylene terephthalate, still used today for the production of films.