VINEGAR SYNDROME
Vinegar syndrome is a term used to describe the chemical reaction that goes on during the deterioration of cellulose triacetate film support. When cellulose triacetate begins to decompose, ‘deacetylation’ occurs and the acetate ion reacts with moisture to form acetic acid, producing a vinegar odor when the can is opened. The presence of the odor does not mean the film has degraded, but rather that the reaction is taking place. However, the reaction is continuous, and once started, it cannot be stopped or reversed. In fact, the reaction is autocatalytic, which means it feeds on itself and speeds up over time. The acid produced can also react with the dyes in color films, causing dye fading and damage to both the image as well as the base.
(NATIONAL
FILM AND SOUND ARCHIVE OF AUSTRALIA)