At the end of November 2018 I was invited to attend the international conference on NANOmaterials for the RESToration of works of ART, (NANORESTART ), held at the National Museum of Denmark in Copenhagen.

The conference marked the conclusion of the Nanorestart European research project – mentioned previously in this blog here:

Gels in Conservation

The research project focused on nanotechnologies and the conservation of contemporary art.  Treating contemporary art is a major challenge for conservators, due to the complexity and variability of the materials used – often those which are new and untested, or materials originally intended for other purposes, or involving the mixture and use of incompatible materials together in one artwork.  To date, there has been a lack of established conservation materials and methodologies that can safely tackle the often extremely fast degradation of the materials of these artworks.

The core of the research project was to develop new tools, innovative materials and treatment techniques in response to genuine conservation needs for the preservation of modern art.  This final conference discussed five of the product families and 15 key product solutions for surface cleaning, consolidation of fibrous materials, coatings to protect metals and plastics and a sensing and diagnostic system for degradation products, developed as a result of the project.

Of most relevance to me, for practical conservation purposes in the field in which I work, were the Nanorestore water-based chemical gels.  These gels can be used with water or loaded with different cleaning fluids, with different formulations of both gel, and cleaning fluid, allowing adaption to the specific substrate to be treated and the substances to be removed.

The mechanical properties of the chemical gels (PVA-based cross-linked hydrogels) mean they are easy to remove without leaving residues – traditional (physical) gel systems can be hard to remove from the cleaned surfaces, the gels are also non-toxic and can be reused a number of times.  They are ideal for the cleaning of water-sensitive (painted) surfaces, due to the minimization of the water or solvent involved in the cleaning process, therefore avoiding the risk of swelling, or tidemarks – vital on water and solvent sensitive surfaces.  By holding the cleaning solutions in a gel, the risk of abrasion, which can occur to sensitive surfaces using tradition cleaning methods involving the use of brushes, sponges or reworking cotton swabs, is also avoided.   The different gel formulations have good surface adaptability to surface texture and contour, good adhesion and handling properties, which makes them useful for curved or irregular surfaces, while using these gels systems also allow specific and selective treatment to different areas which behave in different ways.

The conference opened with a keynote speech by Professor Piero Baglioni, professor of Physical Chemistry at the University of Florence and director of the Italian Research Center for Colloid and Nanoscience (CSGI) which outlined the methods and materials for the consolidation and cleaning of works of art, covering microemulsions, chemical/physical gels, sticky gels, peelable gels and anti-corrosion and self healing systems available to conservators.  He reviewed the most significant achievements in the field, focusing on those systems obtained by the two European research projects: Nanorestart, and the earlier Nanoforart.  His talk covered the use of these materials in works of art by Michaelangelo, Beato Angelico, Piero della Fracesca, Picasso, Lichtenstein and Pollock.  During his address, he also showed chemical gels used with very successful results on site on a wall painting conservation project in Denmark, which was of particular interest to me, with the wall painting in the project appearing to have very similar characteristics and dirt deposits to those commonly faced by wall painting conservators in the UK.

The following papers covered specific research and case studies with the various materials, including the use of the chemical gels at the Tate, London,  in the conservation of Lichtenstein’s Whaam! and Eva Hesse’s Addendum – with treatments focused on the removal of deposited soiling.  Their use on the removal of grime and dirt from unvarnished surfaces and the use on non-original varnishes – on two Jackson Pollocks and Picasso’s The Studio at the Peggy Guggenheim Collection in Italy was also detailed.

These hydrogels are already in production and available from CSGI in Florence:  Later next year they will be also available from the conservation suppliers Deffner and Johann,

Although not yet in commercial production a series of organogels and sticky gels – also developed by CSGI – and produced for use with organic solvents, were discussed in papers, and outlined in a poster on a research project at the University of Amsterdam on surface treatment of a Karel Appel from the Rijksmuseum.  These organogels are expected to be available commercially next year.

Samples of all the Nanorestart products and materials were available, while chemists and scientists involved in the development of the systems were also there to showcase and demonstrate the products and to answer questions.  I picked up samples of the hydrogels produced by CSGI, and have just ordered their hydrogels test kit as well as the same gels in gum and pen form, and look forward to testing the products in my studio.  Although these gels were developed primarily for modern art, I am excited about their potential also for lifting the heavy dirt layers which commonly cover the painted surfaces in Egyptian tombs – the gels would be ideal as they are specifically developed for the treatment of delicate and water sensitive surfaces – precisely the surfaces of an Egyptian tomb painting.

Altogether the conference was an illuminating experience, with some really impressive research and materials produced, which appear to have added considerably to the tools conservators will have for the conservation of contemporary art.

Finally, the research and project results from the NanoRestArt project will be published together in an edited volume.  As soon as there are details on its publication and availability I will add the link here.