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VINEGAR SYNDROME. Before and After Treatment of a 4”x5”
cellulose acetatenegative by stripping the image pellicle from the deteriorated
acetate support.
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When photographic film with a cellulose acetate support
begins to deteriorate we say it has vinegar syndrome because it forms acetic
acid (among other deterioration byproducts) and smells like vinegar. The
acetate support also shrinks and becomes brittle eventually pulling away from
the gelatin image layer in patterns often called channeling. The plasticizer in
the acetate support comes to the surface and forms small bubbles between the
acetate support and the gelatin image layer. With all this deterioration and
deformation it becomes impossible to print or scan the negative and get a good
quality result. Cold storage is the only way to slow down this deterioration
process, but it can’t reverse deterioration that has already occurred. So for
some negatives it is necessary to separate the very thin gelatin image layer
from the deteriorating support. This technique of “emulsion stripping” was
first pioneered in Canada in the 1960s as a photomechanical layout technique
for combining graphic elements in the creation of camera ready art for
printing. It was adopted in the United States also for graphic arts purposes in
the 1970s and by the 1980s was being used for the first time as a conservation
method for deteriorated acetate negatives. It turns out that even after all the
dramatic deterioration of the acetate film base, the gelatin image layer is
usually still OK, and can be separated, scanned, and then stored safely. The
new digital image file can then be written back to a new sheet of
polyester-base film or stored in a digital repository. Gawain Weaver Art
Conservation has been performing this process for several years. Please contact
us to discuss your project.
