Nitrocellulose, celluloid-grade

Fortunately, the less specialized formulations do not employ such a difficult malerial in fact, only rarely does one find a water-soluble colloid. A frequently found binder material is lacquer-grade nitrocellulose (MIL-N-244A, Grade D, sometimes also Grade A), dissolved in acetone (O-A-51) or other low-boiling solvents such as ethyl acetate. Celluloid (MIL-B-10854) solutions in acetone are sometimes preferred. Usual amounts are 1.8-4.0% on a dry basis. 

Nitrocellulose of 11.8-12.3% N intended for celluloid manufacture is obtained in a way resembling the production of lacquer-grade material with the exception that the viscosity of the product is not of such decisive importance. Low viscosity of the nitrocellulose can cause the celluloid gel to be brittle, however. For this reason care should be taken to keep the viscosity above a certain limit. The essential stabilization can be carried out in boilers without recourse to autoclaves, but in order to shorten the stabilization process it is possible to carry out the kiering in autoclaves, the process then requiring only a few minutes. 

In 1855, the moldable features of collodion were exploited by the British inventor and chemist Alexander Parkes, who marketed the material as Parkesine. Combs, earrings, buttons, bracelets, billiard balls, and even false teeth were manufactured in his factories. Parkes chose to focus more on quantity than on quality, however. Because he used low-grade cotton and cheap but unsuitable solvents, many of his products lacked durability, which led to commercial failure. In 1870, John Hyatt, a young inventor from Albany, New York, discovered that collodions moldable properties were vastly improved by using camphor as a solvent. Hyatts brother Isaiah named this camphor-based nitrocellulose material celluloid. Because of its greater workability, celluloid became the plastic of choice for the manufacture of many household items. In addition, thin transparent films of celluloid made excellent supports for photosensitive emulsions, a boon to the photography industry and a first step in the development of motion pictures. 

Nitrated papers which are based on highly purified wood pulp and other fibres used to manufacture the highest grades of nitrocellulose for use as celluloid, films, and lacquers. 

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