An investigation into a consolidation treatment for flaking autochrome plates

Historic autochrome plates that do not have a final varnish layer or cover glass often exhibit flaking or lifting edges. In some cases, larger areas of delamination of the emulsion can be observed. A common stabilizing treatment for uncovered plates, which allows for safe handling and storage, is to seal the autochrome using a cover glass. However, plates that exhibit severe delamination cannot be safely sealed without prior stabilization of the fragile and brittle emulsion. This paper presents technical information on the manufacture of the autochrome plate and describes testing performed to find a treatment to consolidate flaking/delaminating emulsions. Reproduced components of the autochrome screen and historic autochrome plates were used for testing and examination was performed using tools such as the stereomicroscope and the scanning electron microscope.