Effect of Five Essential Oils as Green Disinfectants on Selected Photographic Prints: Experimental Study

Abstract

Albumen, silver gelatin and chromogenic prints are found abundantly among photographic collections in Egypt. Due to the uncontrolled environment in archives and libraries, this precious visual heritage with its high protein and cellulose content provides the right culture medium required for fungal growth. Many essential oils have been proven to have antibacterial and antifungal properties. Essential oils offer a safe alternative to other common disinfection methods; however, their effect on the properties of photographs have not received much study. This paper studies the effect of vapors of anise, cinnamon, clove, lavender and thyme oils on albumen, silver gelatin and chromogenic prints, to find a proper disinfection method that is user-friendly and environmentally safe and respects the nature of photographic materials. Essential oils were provided by the National Research Center (NRC) in Cairo, Egypt. Artificially aged albumen prints, and naturally aged silver gelatin and chromogenic prints were exposed in desiccators to the selected essential oils in the vapor phase for a period of 5 days. All samples were artificially aged at a temperature of 80°C and 65% RH for a period of 5 days to study the long-term effects of the tested treatments. Treatments were evaluated using several techniques including visual inspection, microscopic inspection, colorimetric measurements, and attenuated total reflectance Fourier transform infrared spectroscopy. Results showed that all tested essential oils had a very slight effect on the tested photographic samples; however lavender oil was found to be the best option, specifically in terms of preserving the chemical properties of the photographic surfaces.