Applying chitosan to increase the fungal resistance of paper-based cultural relics.

Abstract

Paper-based artworks and documents often suffer damage from the growth of fungi. Biological damage is mainly brought about by unsuitable environmental conditions and often results in discoloration and structural damage to the basic components of the materials or to the essential additive constituents. Mold growing on paper products is one kind of bio-deterioration; moldy stains on paper obviously decrease the life of rare books, paintings, and art crafts, and make them more difficult to preserve. Chitin, after cellulose, is the 2nd most abundant material in nature. Chitosan is a substance obtained by the deacetylation of chitin, the principal component of many living things, including crustaceans, insects, and fungi. Because of their superior properties and abundance, chitosan and chitin are extensively commercially utilized worldwide. Due to the fact that chitosan is a cationic polymer and a cationic polyelectrolyte, it shows superior antimicrobial properties. The purpose of this study was to investigate the feasibility of using chitosan as a possible material to increase the fungal resistance of paper-based cultural relics. Filter paper treated with 1.5% deacetylated chitosan showed the best fungal resistance effect; the higher the concentration of chitosan, the more superior was the fungal resistance effect obtained. At the same concentration, the higher the deacetylation of chitosan, the better the fungal resistance effect was. The application of chitosan to increase the fungal resistance of paper-based cultural relics can be a viable alternative conservation strategy for paper-based artifacts and archives.