Journal of Film Preservation - FIAF

References
1 F.Catalina, A.Del Amo, “Cellulose
triacetate motion picture film bases. A
descriptive analysis and a study of the
degradation and preservation -
Related variables”, FIAF Madrid´99, Ed.
Ministerio de Educación y Cultura,
Filmoteca Española, Madrid, Spain,
1999.
2 “The book of film care”, Eastmant
Kodak Company, Ed. P.L.Gordon,
Rochester, 1983; “Conservation of
Photographs”Eastman Kodak
Company, Rochester, 1985.
3 M.Edge, N.S.Allen, T.S.Jewit, C.V.Hory.,
“Fundamental aspects of the
degradation of cellulose triacetate
base cinematographic films”,
Polym.Deg. Stabil., 25, 345, 1989;
M.Edge, N.S.Allen, J.H.Appleyard,
T.S.Jewit, C.V.Hory, “Degradation of
historic cellulose triacetate
cinematographic film: Influence of
various film parameters and
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4 A.Tulsi Ram, “Archival preservation of
photographic films – A perspective”
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5 “Storage guide for acetate film”, J.M.
Reilly, IPI –Image Permanence
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Figure 14: Gelatine viscosity decay (5 % solution, 37ºC) versus time of biodegradation with
Bacillus and Pseudomonas 29 .
such as Salmonella,Kluyvera, Staphylococcus, Pseudomonas,
Burkholderia, Enterococcus, Yersinia, Streptococcus and Bevundimonas.
Micro-organisms identified as Bacillus and related endospore forming
genera als found. All these isolated show a capability to liquefy
gelatine. Endospore-forming isolates were assigned to Bacillus
licheniformis, B. fumarioli, members of the B. Cereus group, B. badius, B.
coagulans, B. subtilis, Brevibacillus agri, Alicyclobacillus acidocaldariu,
and a yet undescribed Paenibacillus species. These micro-organisms can
destroyed the gelling properties of the gelatine which is of particular
importance in photographic applications. Contamination with aerobic
endospore formers, which can produce different proteases, including
gelatinases31 , is a widespread problem. This is especially important as
this group of bacteria is ubiquitous due to its broad nutritional
versatility, and the wide pH and temperature range tolerance. In
addition they forms endospores which have a much higher resistant32 to heat, chemicals, irradiation and desiccation than vegetative forms.
This is the main reason of their general occurrence in gelatine
materials. In the photographic industry, gelatine quality requirements
are very important, and a constant monitoring programme of the
microbiological quality is necessary to avoid contamination.
Micro-organisms in Archives
There are many historical buildings used as archives after the structure
has been adapted, as well as new buildings. Storage conditions are a
most important consideration,since temperature and humidity are key
factors in the film conservation. The biodeterioration or the
biodegradation of the photographic emulsions in the presence of
micro-organisms is a real threat to collections in humid climate
regions. In particular, the risk is greatest where the annual relative
humidity is well above 70%, and where the storage conditions are not
constant, or sufficiently controlled33 , as specified by the International
51 Journal of Film Preservation / 67 / 2004