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\0 VINEGAR SYNDROME

Peter Goed
Vinegar Syndrome has been making big news with tilm collectors in all f(mnats for quite some
time. Any signs of this syndrome within a collection is of paramount concern as it can spread to
every other film within near distance to it and effectively destroy a whole collection within a short
period oftime. Many collectors are put off by the very word Vinegar, without really understanding
what it is.

1 -Symptoms

The easy way to tell Vinegar Syndrome is by the pungent odour that emanates from a film, and can
only be likened to the acetic smell of vinegar. Although Vinegar Syndrome varies in intensity and
smell, even the slightest hint of a smell that remotely resembles vinegar is of concern to the film
collector because it is an indication that the film stock is in a state of deterioration. Ultimately, the
slightest of smells will deteriorate to extremely unpleasant smells, and along with this the film will
buckle, soften and become un-runable.
To understand just what Vinegar Syndrome is we have to firstly look at how the film stock is made.
Modern 35mm Safety Film stocks from the early 1 950s, and l6mm film from the very beginnings of
16mm in the early 1920s until today, are made predominantly from a base called "Triacetate".

Triacetate is a polymer, manufactured from a chemical reaction involving cellulose and acetic acid,
just as Nitrate film is made from cellulose and nitric acid. Because of the way the film substrate is
made, there will always be an inherent amount of 'free' acetic acid, generally trapped between the
substrate and the emulsion. This is normal, and under cool conditions of storage, around I 0 degrees
Celcius, Vinegar Syndrome may never make an appearance.
2- Causes

The trouble really begins with heat and high humidity. These cause the film to start doing a back-
flip by trying to break down into the two substances that formed the base material in the first place,
i.e. cellulose and acetic acid.
The area of the film that seems to be the most affected is between the substrate and emulsion. A
build up of humidity, combined with heat will cause acetic acid to burst through the emulsion as a
gaseous substance, creating microscopically small holes through the emulsion as it escapes into the
air and gives us the typical vinegar odour that exudes from acetic acid.

With time the symptoms will get worse, with acidity levels rising sharply in relation to time, and
film deterioration becoming extreme within a matter of only a few months.
3 -Stabilisation

It is possible to stabilise Vinegar Syndrome in several ways, but it is extremely important to isolate
any affected film from other 'good' film as soon as the syndrome is first detected.

Stabilisation is at best a short-term solution, often involving some expense. Film may be placed in a
refrigerator or freezer to lessen the effect of deterioration, or a commercial substance such as
'Molecular Sieves', may be placed inside cans holding affected film.