EVALUATION OF COATED LASER PRINTED INFILLS FOR USE IN MANUAL RESTORATION OF LOSSES IN SILVER GELATIN PRINTS

Document Type : Original Article

Authors

Conservation Department, Faculty of Archaeology, Cairo University, Giza, Egypt

Abstract

The significance of photographic collections to our shared cultural heritage has 
become apparent; and therefore, the focus on their preservation has intensified. 
Photographs made during the last one hundred years belong to a class known as 
silver gelatin prints. A silver gelatin print is mainly composed of the primary 
support (i.e. paper), the baryta layer (i.e. fine particles of barium sulfate in gelatin 
layer) and the gelatin binder layer carrying the final image material (i.e. metallic 
silver particles). One major issue in photograph conservation field repairing losses 
in silver gelatin prints since the reflective index and texture of silver gelatin prints 
are difficult to simulate. In 2017, a combined manual and digital restoration 
technique was proposed by Yosri for the restoration of losses in silver gelatin 
prints. Results proved the stability of long-term stability of laser printing 
compared to inkjet printing. However, analytical assessment techniques showed 
changes in the appearance of the samples post artificial ageing. The main aim of 
this paper is to assess the efficiency of selected coating materials (i.e. methyl 
cellulose, Klucel G, gelatin and Funori) in improving the stability of laser printed 
infills to be used in damaged silver gelatin prints. Long-term stability of the 
coated printed samples will be evaluated after exposure to humid heat artificial 
ageing at a temperature of 80°C and 65% RH for 5 days using several techniques 
including visual inspection, microscopic inspection, pH value measurements, 
colorimetric measurements, and Fourier transform infrared spectroscopy (FT-IR). 
The second part of the study involves the treatment of selected vintage silver 
gelatin prints suffering from various damage forms, mainly losses and surface dirt. 

Keywords