Celluloid is one of the most beautiful raw materials in the universe of fountain pens. We could summarily describe it as the most brightly colored and stable material ever used for their production; but to understand the true complexity of this seemingly simple material, we need to examine both its history and the industrial process from which it is born.
Celluloid is a very stable material but at the same time highly flammable. It is possible to verify both of these qualities with the help of a ping-pong ball. After playing and counting the many hits it can take before breaking, wrap the pieces of the broken ball in aluminum foil and light the wrapper: a flame of surprising intensity will be released.
The development of celluloid began around 1845, as a response to the new industrial need to find a substitute for certain natural materials such as tortoiseshell, ivory and mother-of-pearl. All these raw materials, donated directly by nature, already began to be scarce at the time and costs consequently rose.
Nitrocellulose is obtained from cotton treated with two acids, nitric and sulfuric. A subsequent processing with alcoholic camphor, heat and pressure, produces celluloid, which however requires a further treatment which reduces the camphor content and allows the material to harden. The ingredients of this new industrial cocktail were all natural and easy to find (here is an interesting video on the production of the material; https://www.youtube.com/watch?v=3sLvjxV0Bj8&t=10s ).
Beginning around 1890, celluloid came into use for the mass production of many products, as it proved capable of imitating, almost perfectly, materials such as horn, ivory, precious and semi-precious stones, coral. It was stable, and lent itself well to both hot modeling and lathe work.
But the most appreciable quality was, and remains, the almost infinite variety of colors and patterns obtainable from the coloring of the raw material. In its natural state, celluloid is a semi-transparent substance, straw-yellow in color and, depending on the level of camphor, of either a gelatinous or solid consistency.
It is during this stage of production that coloring agents can be added. Or, for example, blocks of variously colored celluloid can be cut into sheets to compose new blocks with alternating layers, thus obtaining the striped effect that we know, for example, thanks to the Parker Vacumatic of the 1930s.
The marbled or mottled effect, on the other hand, is obtained by adding flakes of celluloid of different colors to a fluid mixture and subsequently annealing everything to obtain a new block. The higher the residual camphor rate in celluloid, the softer the material. To obtain a solid material, ready for use in the production of fountain pens, it is necessary to subject it to a seasoning process which allows the camphor to evaporate almost completely. During this stage of its processing, the material, still in a highly flammable state, shrinks continuously.
Likewise, a pen made from material that is too fresh will decrease in diameter over time. And since celluloid can take up to 12 months to fully cure, the temptation to use "young" celluloid was great, especially during times of unexpected sales increases (again a couple of instructive films on the manufacturing process which in fact applies almost indifferently to celluloid and cellulose acetate, still widely used, the latter, in the production of eyeglass frames: https://www.youtube.com/watch?v=kLwN0lHGQ-c ; https://www.youtube.com/watch? v=TOf9rd31sQ8 ) .
As early as 1890, celluloid was successfully used in many industries. But it took another 30 years before it was well accepted as a material for fountain pens. From 1924, the year in which Sheaffer marketed its first, highly successful celluloid pens, all its competitors were forced to follow suit. But some were quite recalcitrant, at least for a while. Waterman countered by launching ripple hard rubber in several new colors, and in early 1928, Mont Blanc circulated a warning letter regarding the new pens among its dealers.
It is not possible to produce a high quality pen, in celluloid, by means of fully automated processes. The best quality pens are turned from solid celluloid bars with long periods of seasoning interspersed with the various processing stages.
Stipula is among the rare pen factories in the world today that still produce celluloid fountain pens. Both from very long seasoned celluloid which the factory keeps in its aging ovens; both by recovering original celluloid from historic stock that it took over from old disappered factories in Italy .