Contributors: Michell Gilman, Melissa Price, Alex Garcia-Putnam
Vinegar syndrome is a chemical of degradation that occurs with cellulous acetate film and is characterized by an obvious vinegar smell. A process in which acetate film begins to degrade. This applies to media (cinematographic and photographic film, microfilm) made with acetate backing; most film of this type was made prior to 1980. The degradation process releases acetic acid, the same substance in vinegar that gives it its smell which is the identifying characteristic of the degradation process.
acetate film base degradation
Synonyms in English
|French||syndrome du vinaigre|
|Spanish||síndrome del vinagre|
|German||Essig-Syndrom, síndrome do vinagre|
Vinegar syndrome effects acetate or safety film. This type of film is deemed safe as a comparison to the highly flammable nitrate film. Acetate film, made of plastic, degrades in a roughly predictable manor.
The chemical deterioration process of film materials made from cellulose acetates (diacetate, triacetate, acetate propionate, acetate butyrate) is known as "vinegar syndrome" Bereijo, 2004. Many films made prior to 1980 were constructed of these materials are organic in origin and can last no more than 100 years before signs of deterioration begin [[#ref 4| Heritage Archives]. Once the process begins, it cannot be stopped; the film itself cannot be saved, but the information it holds can be preserved by duplication onto modern film Bereijo, 2004.
Cellulose acetate film became the standard material used for cinema film when nitrate film was discontinued in the 1950s, although it has been used since the beginning of cinema. It was considered too expensive in the early years of cinema and was used primarily for smaller-gauge films at that time.Aubert, 2003. It was not until the 1980s that "film archivists noticed acetic vapor coming out of triacetate film cans, and the film inside had become limp. This decomposition became known as the “vinegar syndrome,” taking its name from the characteristic odor of the vapor" Aubert, 2003.
The degradation of the film involves the release of acetic acid. The film is made of a sheet of cellulous acetate that provides a base for the image layer. The deterioration starts in the cellulous layer and diffuses up through the image layer, creating an acetic or vinegar odor ( Image Permanence Institution 1993). Shrinkage and brittleness are also symptoms of this syndrome ( National Film Preservation Foundation). This degradation is characterized by a drying and shrinking of the film, embrittling, and the strong vinegar smell that gives it its name (National Film Preservation Foundation 2013).
High humidity combined with high temperature or extreme changes in temperature are causal factors of vinegar syndrome. "Decomposition of triacetate films is caused by hydrolysis of the acetate groups, which results in the formation of acetic acid. This acetic acid in turn increases the rate of hydrolysis, which renders the decomposition autocatalytic" Aubert, 2003. Poor storage conditions are to blame for the onset of this process, and it is accelerated when chemicals remain as a result of poor developing techniques during film development Aubert, 2003.
Vinegar syndrome is infectious as it gives off acidic vapors, causing other film in the immediate area to degrade as well ( Bigourdan 2000). The process must be identified early on because it speeds up with time. Special test stripes can be employed to test for vinegar syndrome, but little can be done once it onsets (Reilly 1993). A-D strips test for the severity of degradation of cellulous acetate film ( National Film Preservation Foundation).
Vented enclosures may help to slow deterioration since non-vented or sealed enclosures trap acids and speed up the decay process ( Bigourdan 2000). Use breathable enclosures and store in a low temperature and low relative humidity. Film in an advanced state of decay should be duplicated and placed in cold storage, or frozen ( National Film Preservation Foundation). Proper storage and handling practices: using gloves, and storing in low light environments, can prevent vinegar syndrome almost entirely.
Aubert, M. 2003. Materials issues in film archiving: a French experience. Materials Research Society bulletin.
Bereijo, A. 2004. The conservation and preservation of film and magnetic materials (1): film. Library Review 53(6):323-331.
Bigourdan, Jean-Louis. 2000. Vinegar Syndrome: An Action Plan. The Vinegar Syndrome: A Handbook, Prevention, Remedies and the Use of New Technologies 45-59. https://www.imagepermanenceinstitute.org/webfm_send/308 (accessed 04/27/14).
Feller, R. L. 1994. Chemical research in conservation: the deterioration process. Journal of the American Institute for Conservation 33(2):91-99.
Image Permanence Institution. 1993. Acetate Film Base Deterioration: The Vinegar Syndrome. https://www.imagepermanenceinstitute.org/resources/newsletter-archive/v12/vinegar-syndrome(accessed 04/27/14).
National Film Preservation Foundation. Vinegar Syndrome. http://www.filmpreservation.org/preservation-basics/vinegar-syndrome (accessed 04/27/14).
Reilly, JM. (1993). Instructions for Using the Wheel, Graphs, and Table: Basic Strategy for Film Preservation. https://www.imagepermanenceinstitute.org/webfm_send/299
Vinegar Syndrome. 2010. Heritage Archives. http://www.heritagearchives.org/vinegarsyndrome.aspx (accessed 04/13/14).