A Vacumatic with a very tansparent celluloid

Celluloid is a material invented around 1863,[1] produced from the processing of nitrocellulose and pigments in a solution of camphor and ethyl alcohol. The material when heated (about 60°) becomes malleable and may be bent and also molded; for this is considered as the first thermoplastic resin produced.

Celluloid is an elastic material and it is shatterproof, shock resistant and waterproof. Its origin stems from the search for a replacement for billiard balls production, but was soon used for many other applications, such as combs, knife handles, and especially as support for photographic film. Today, apart from some fountain pens, is used for ping pong balls and guitar picks

Celluloid can be a very durable material, but it requires a rather lengthy process in particular for drying that allows you to remove residual moisture from the material. If this does not happen in fact it can give undergo a crystallization, becoming extremely fragile. Another common problem with celluloid pens is the discoloration, present mainly in the lighter colors such as pearl or jade green; this is typically due to the release of sulphurous gases from the rubber sacs. Furthermore, the celluloid is extremely flammable, and is not the case to heat a celluloid made pen with an open flame.

The celluloid name was the trade name given to this material from the first producer, the Celluloid Manufacturing Company, which held its trademark rights; so in the following years it was called, especially by fountain pens manufacturers, in many different ways: Radite by Sheaffer, Permanite by Parker, Pyroxalin by Eversharp, Aurolite from Aurora, Coralite by Carter ...

In addition to the direct use, celluloid lends itself to combination with other materials, in particular Carter realized a characteristic iridescent material, named Pearltex, combining the celluloid with nacre. A similar effect is in celluloid called Abalone by Sheaffer.

Example of different colors

Per le sue caratteristiche di resistenza meccanica, infrangibilità, impermeabilità, per la facilità di lavorazione e ma soprattutto per l'infinita capacità di colorazioni diverse, a partire dalla metà degli anni '20 la celluloide divenne il principale materiale usato dai produttori di penne stilografiche e rimase tale fino agli anni '40 quando iniziò la diffusione delle varie resine plastiche.

Benché su alcuni testi sia riportato che la celluloide venne introdotta sul mercato dalla Sheaffer in realtà la prima azienda americana ad averla usata estensivamente nella sua produzione è stata la LeBoeuf, che la utilizzò per le proprie penne a partire dal 1920 circa grazie ad un brevetto (nº US-1302935) per la produzione di tubi in questo materiale, la Conway Stewart ne contesta il primato, asserendo di essere stato il primo costruttore ad aver prodotto (sempre in quegli anni) la prima penna in celluloide.

In realtà esistono riferimenti alla produzione di penne in celluloide fino dal 1905[2] ma in questo caso si tratta comunque di celluloide nera, e non di quella celluloide realizzata in molteplici colorazioni e motivi che diventerà il materiale più significativo a partire dalla seconda metà degli anni '20.

Note

  1. the invention is attributed to John Wesley Hyatt, but there are several predecessors (its origins date back to the work of Alexander Parker in England); also the exact date of its origin is uncertain, as usual you can see details in the Wikipedia page on celluloid.
  2. David Nishimura in questa discussione fa riferimento ad un articolo del 1905 che parla di penne in celluloide (nera).

Riferimenti Esterni

  • [1] Evaluation of Cellulose Ethers for Conservation
  • [2] Sulla degradazione dei plettri
  • [3] Celluloid objects: their chemistry and preservation
  • [4] degradazione delle plastiche
  • [5] Ricette di solventi per celluloide
  • [6] Ancora ricette
  • [7] Discussione sul forum