Saturday, November 17th

Second Day


Third Session – CANVAS AND PAPER SUPPORTS: the choice of methods

Chairman: A. Casoli, University of Parma


 9.00    The de-acidification of canvas paintings

S. Hackney, Senior consultant for Conservation Science, Tate, London

Concern for physical damage dominates our perception since it is clearly associated with physical events. In comparison, chemical processes of deterioration are relatively slow and difficult to identify with specific events, until they are revealed as physical damage. In most major cities, since the beginning of the nineteenth century, historic paintings have been exposed to long periods of pollution and have over time absorbed sulfur dioxide on their canvases. There is no shortage of evidence from paper science that cellulose deteriorates rapidly in acid conditions and can be preserved by the removal of the acidity. De-acidification of canvas has been practised for many years and long-term harmful effects have not been detected. It might be argued that de-acidification is an irreversible treatment, but acid hydrolysis is a continuing danger and also irreversible.


 9.20    The use of nanomaterials for the deacidification of book and archival products

R. Giorgi, G. Poggi, N. Toccafondi, P. Baglioni

CSGI & Department of Chemistry – University of Florence

Nanotechnology is providing new materials for the deacidification of manuscripts, books, and other cellulose-based objects. Humble calcium and magnesium hydroxide can be successfully used as a nonaqueous dispersions to control pH acidity and inhibit oxidation processes favoured by iron gall-inks.


 9.40   pH and DP studies of canvas paintings

M. Oriola1, M. Strlic2, G. Campo1, A. Mozir3, A. Nualart1, C. Ruiz1

1Conservation Section, Faculty of Fine Arts, University of Barcelona, Spain

2Centre for Sustainable Heritage, The Bartlett School of Graduate Studies, University College London, UK

3Faculty of Chemistry and Chemical Technology, University of Ljubljana, Slovenia

Acidity (pH) and degree of polymerization (DP) are two important parameters to know the condition of the canvas support in a painting. However, not that many paintings have had these two parameters analysed. The present study offers the results of measuring the pH of 179 samples of canvas support and the DP of 95. This allowed us to learn about the typical pH and
DP values of paintings, which were mainly from the 19th to the 21st century.


10.00   Lyophilizing as a method for saving flooded volumes and books subjected to a   microfungi attack

F. Troiano1, N. Barbabietola1, P. Colaizzi1, M. Montanari2, P. Livi3, F. Pinzari1

1ICRCPAL, Ministero per i Beni e le Attivita Culturali, Roma

2Dipartimento di Protezione Valorizzazione Agroalimentare, University of  Bologna

3Restorer at Frati & Livi s.r.l, Bologna

The present work concern with the effects of freeze drying treatment on biodeteriorating fungi that attack the wet paper. The study is based on the treatment of paper samples infected with fungal filamentous species that are frequent on paper soaked in water. Results indicate that freeze-drying is able to kill or suppress the fungal mycelium, but only in part (and in various ways depending on the species) spores and conidia.


10.20   Farnesia Arbor, painted graphic artwork on lined paper:  from preliminary characterization to de-acidification treatment.

A. Casoli1, C. Isca1, F. Romagnoli3,  I. Saccani2,  F. Saggese1

1University of Parma


3Restorer, Parma

Following chemical and physical analysis on Farnesia arbor (characterization of paper fibers, glue and materials, surfeace pH mesurements), a new method of deacidification was tested: a water solution of Ca(HCO3)2 was experimented and applied by aersol. This step is a part of a wider conservation path, including a partial removing of the varnish and the flattening of planar deformations.


10.40   Round table: former speakers facing
“Deacidification intervention opportunities” - audience’s questions


11.00   Break


11.30   Giuseppe Pellizza da Volpedo: conservation of graphic artworks related to the paintings Il Quarto Stato and Sul fenile , from the Atelier-Museum in Volpedo

C. Frosinini1, L. Montalbano2, S. Micheli3

1Director of Drawings and Prints Conservation Department,Opificio delle Pietre Dure, Florence

2Technical Director of Drawings and Prints Conservation Department,Opificio delle Pietre Dure, Florence

3Restorer cooperating with Opificio delle Pietre Dure, Firenze

Since 2007 the Department of prints and drawings conservation of OPD in Florence, in collaboration with the Associazione Pellizza da Volpedo,  has restored tree preparatory drawings for the paintings “Sul fenile”(1893) and “il Quarto Stato”(1898 e il 1901) of  the Volpedo Studio-Museum, taking also care of preservation and exhibition point of view inside the painter atelier, donate by the two Pellizza daughter to Volpedo town in 1966 and open to the public in 1994.



Chairman: Oscar Chiantore, University of Turin


11.50   The influence of size and ground layers of a canvas on its stiffening and orthotropy

A. Roche, engineer and conservator LARCROA, Paris, France

The qualities of a canvas and the preparation are essential to the conservation works. Coated fabrics must meet certain quality criteria based on the mechanical properties. Once stretched on a frame and prepared, coated canvases are the foundation of the paintings, which guarantee the durability and aging of the paintings in time. This study is divided into two parts: a numerical approach and an experimental approach. The objective of our study is to determine the best criteria for a quality coated canvas can play a better role in the composition of the support. We have therefore chosen for the experimental part 5 linen and 5 polyester fabrics, plain weave, but with different textures. They were chosen among the fabrics used in the field of fine art and conservation. The study guides our choice of fabrics and coatings, for a raw canvas, even though of a good quality, can appear unsuitable, once prepared and ready to use.


12.10   The choice of consolidating materials: concerns and solutions

R. Ploeger1, E. René de la Rie1, C. McGlinchey 2

1National Gallery of Art, Washington DC, USA, 2Museum of Modern Art, New York, NY, USA

This international collaborative project aims to understand the chemical and mechanical properties required for an ideal consolidating adhesive, and to develop a new heat-seal adhesive product for the consolidation of paintings. A first step is to investigate BEVA 371, an ethylene-vinyl acetate (EVAc) based conservation adhesive, and to improve its stability while maintaining its useful thermomechanical properties. Preliminary results will be presented.


12.30    Wood treatment with metal nonpolar matrix chelants and functionalized silica gels Notes on the preparation and chemical-physical characterization

M. Berlanda1, G. Predieri1, O. Allegretti2

1University of Parma

2C.N.R.-IVALSA, Trento

The present research aims to characterize the physical-mechanical characteristics of wood samples processed with experimental preserving products: preservative solutions with zinc chelates and copper amine complexes grafted to functionalized silica gel.


12.50   Stuffing everything we know about mechanical properties into one collection simulation

S. Michalski, Canadian Conservation Institute


13.10   Lunch break



Chairman: A. Giordano, CESMAR7 Vicepresident


14.30   The big canvas from the ceiling of the Galleria Dorada of Gandia, Spain. Dismantling and reallocation, restoration and elastic refunctionalization of original stretchers

A. Iaccarino Idelson 1, C. Serino 2

1CARLO BO University, Urbino

2Equilibrarte s.r.l., Pesaro

The presence of wide gilt frames made the removal and handling of the paintings complex operations. The original strainers were conserved; an elastic system based on the free flow of canvas on perimeter made it possible to reach a negligible sagging with a small, even and measured tension. Rails in the ceiling allowed installing the paintings trough one room, with very limited intervention on the frames.


14.50    Protective facing for big canvas paintings. Survey of the selected materials for the treatment of artworks from Palazzo Ducale of Gandia, Spain

S. Martin-Rey, M. Castell-Agustí, V. Guerola-Blay, C. Robles-De La Cruz

University Institute for the Restoration of Heritage, University of Valencia, Spain

In several occasions, the large canvas paintings should be routed to the transport from the initial position to the laboratory where they will be restored. Afterwards, they need to be rolled up again once the restoration has finished, to return to their initial position. During this process, the colour protection and the materials used in each of these two phases, must be clearly different, since the conditions of the work substantially change, before and after the restoration. In this paper we present the results and materials developed by a group of researchers from the Institute of Heritage and Restoration of the Polytechnic University of Valencia (Spain), on the way to study an intervention of a large canvas painting, which can be found on the ceiling of the "Galería Dorada", the Ducal Palace of Gandia in Valencia. We show here the study and formal analysis, performed for the transfer and final assembly on the ceiling of the building. The main objective is to obtain the final protection of these paintings, strong adhesive resistance after the rolling up for their transfer, but at the same time, the lightweight material with the minimum moisture that allow us to remove it, without leaving any residue on the original colour surface. Always emphasizing the requirements and not to cause colour changes on paintings after this operation.


15.10   Non-invasive methods for a safe handling of artworks

D. Riggiardi,  Restorer, Milan

During handling or movement, the works of art undergo stresses, strains and sudden changes in temperature and RH. This paper would present shock absorbing and insulating system for artworks, as well as devices to protect them during handling.


Closing Proceedings


15.30   Conclusion

Stefan Michalski, Canadian Conservation Institute