Interfiling 16mm Polyester Film with Acetate film: A Study

Abstract

The University houses motion picture film collections across multiple libraries. Over the past year, efforts have focused on testing these films for vinegar syndrome and visually inspecting them to transfer unaffected films to a 50℉ offsite storage facility. A-D Strips from the Image Permanence Institute (IPI) were used to randomly sample films from the main collection, which includes over 2,500 acetate and polyester-based films stored together for 15 years in a room with fluctuating environmental conditions. During this initial testing phase, several anomalies were observed when testing polyester based motion picture films. The polyester based film that was part of this initial phase recorded results that were in the .5 - 2 range of A-D strip levels. Because polyester film is considered to be the most stable of the types of motion picture film, these results led to questions about the long-term stability of polyester. Primarily, this research project aimed to determine if the positive A-D strips from polyester films were due to their long-term interfiling with acetate film, or if the polyester film was potentially going through its own form of degradation.