AIC's 44th Annual Meeting

This paper will describe and compare different gels used in recent years for conservation treatments. The use of gels may allow for localized treatment, to reduce risk for media layers and to reduce physical stress to paper. To achieve these aim with a gel, a film-forming material which is easy to cut to the correct shape and size is required. This gel must also remain stable to environmental conditions such as pH content and temperature. The material should be very capable of retaining of liquid, such that the liquid is slowly released into the paper; transparent, so we can easily monitor the treatment at any time; non-toxic, so application is safe for the artifact, the conservator and the work environment. It would also be of significant benefit to conservators and institutions if it were affordable and easy to obtain. Polysaccharide gels such as Agar and Gellan Gum are two common products used in a lab. These two physical gels have been proven effective for the cleaning of paper. Studies suggest Gellan Gum has the qualities required and does not leave residues on the paper."Nanoforart" is responsible for the development of another type of gel. The aim of the "Nanoforart" project was to develop nano-technologies for the conservation of cultural heritage. Different products were developed, such as micro-solutions for consolidation of stone and deacidification of paper and micro-emulsion and micellar solutions for the cleaning of surfaces. The team developed chemical gels as a vehicle for new liquid treatments; acrylamide/bisacrylamide hydrogels and a semi-interpenetrating p(HEMA)/PVP network. Chemical gels differ from the physical gel by the strong bond between the macro-molecules. The gel is less likely to break when handling and is less likely to leave residue. Also, the chemical gel acts like a sponge and can be used with a large range of liquids, allowing for the treatment of very water-sensitive artifacts with a pure organic solvent or one of the liquids developed by the "Nanoforart" team. The studies suggest that those chemical gel have better liquid retention abilities when compared to other physical gels. The introduction of rigid gel in paper conservation interventions allow a greater control on the solvent used and reduce physical risk related to manipulation of the objet. In the literature, few authors were interested in comparing and synthesizing the possibilities, advantages and disadvantages of the aforementioned gels for their use in paper conservation. This paper is my attempt to do so.