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manufacture of billiard balls. Hyatt succeeded in
1870 by mixing cellulose nitrate with camphor to
form celluloid. He founded a company known as
the Celluloid Manufacturing Company in 1873. The
use of celluloid was extended thereafter towards the
production of various objects: domestic utensils
and accessories (sunglasses, combs, wallets…),
films, varnishes, etc. But over time, cellulose nitrate
hydrolyses, camphor sublimes, and the objects
deteriorate irreversibly. The poor life expectancy
of nitrocellulose now poses many conservation
problems for museums and archival collections.
Later, industry would offer more durable, safer
synthetic polymer alternatives.
Photography
In 1871, British physician Richard Leach Maddox
introduced the gelatin-silver bromide photographic
process (7). At the time, photographers were using
collodion plates that had to be exposed and processed
within a few minutes following their coating, before
the collodion solvents could evaporate. Gelatinsilver
photographic plates, by contrast, were used
dry; they could be kept in their sensitized state for
months before exposure and could be developed
long afterwards. Thus, gelatin-silver materials could
be manufactured industrially, distributed throughout
the world, stored, and purchased for future use, all
while still retaining photographic sensitivity. The
advantage of the gelatin-silver bromide photographic
plate was unquestionable; it was named “dry plate”.
In 1873, the first dry plates were sold on the market
by the English photographer John Burgess; this
would be a radical break from the primitive period
of photography; now the medium was marked by
mass production. The following year, the Liverpool
Dry-plate Photographic Printing Company was
established, and other companies were to follow,
such as Wratten & Wainwright (1878). The practice
of photography became increasingly accessible
to the general public, no longer exclusive to
professional photographers and a few dedicated
amateurs. New enthusiasts of photography were
the main beneficiaries of the democratization of
photographic activity. This resulted in the emergence
of a flourishing industrial business that produced
major photographic companies in Europe and in the
18
United States. For instance, in France, the Lumière
Brothers Company started the production of
photographic plates in 1880s. The Company began
with an annual production of 18,000 boxes. By
1886, production exceeded 100,000 boxes, and each
subsequent year saw a growth in demand. In 1890, a
hundred workers provided an annual production of
350,000 boxes, and 2,550,000 boxes in 1900.
At the time, heavy and fragile glass plates were
increasingly replaced by a more flexible support
base made of celluloid film. This new base
would aid the invention of cinematography in
1895. Nevertheless, despite excellent physical
and optical properties, celluloid poses serious
problems in archival collections. One issue is that
cellulose nitrate is very flammable, which caused
its banning in the 1950s. This problem, already
known for celluloid, also occurred with films;
over time, cellulose nitrate hydrolyzed, releasing
nitric acid. And if any cellulose nitrate base films
are still in excellent condition after more than a
hundred years, others have already degraded into
powder or a mass of sticky residues, off-gassing
acid fumes. Other cellulose derivatives were used
instead, such as cellulose diacetate, cellulose
triacetate, cellulose acetopropionate or cellulose
acetobutyrate. However, their life expectancies were
overestimated: an alleged promise of a few hundred
years would be reduced to a few decades. Since the
late 1980s, collections have been faced with “the
vinegar syndrome” problem. This phenomenon,
which occurred after about 40 years of storage, was
reported as early as 1954 in film archives in India.
The breakdown of cellulose acetate released acetic
acid (hence the vinegar odour), accompanied by
mechanical weakening of the film. The acid released
into the atmosphere spread the phenomenon to the
entire collection in the vicinity. This deterioration
seemed inevitable, and sped up with increasing
humidity and temperature. Since then, polyethylene
terephthalate and polyethylene naphtalate have been
introduced as a suitable substitute by the polymer
industry, although cellulose triacetate is still widely
used for 35 mm films.
These few examples show the consequences - often
undesirable - of major innovations that were rapidly
adopted and extensively employed in the production