Study of behaviour on simulated daylight ageing of artists¿ acrylic and poly(vinyl acetate) paint films

[EN] This work proposes a multi-method approach that combines advanced microscopy (SEM/EDX, AFM) and spectroscopy (UV-vis and FTIR) techniques. This approach not only characterises the behaviour of the additives of two commercial poly(vinyl acetate) (PVAc) and acrylic emulsion paints but also simultaneously characterises the changes in chemical composition and morphology observed in the paint films as a result of ageing due to the paints being exposed to an intense source of simulated daylight. In parallel, a series of mechanical tests were performed that correlate the chemical changes in composition and the changes observed in the films' mechanical properties. This work was a comparative study between both types of acrylic and PVAc paints. The results obtained are of great interest for the modern paint conservation field as they provide valuable information on the mid- and long-term behaviours of these synthetic paints.Financial support is gratefully acknowledged from the Spanish "I+D+I MICINN" project CTQ2008-06727-C03-01/BQU supported by ERDEF funds and from the "Generalitat Valenciana" I+D project ACOMP/2009/171 and the AP2006-3223 project ascribed to the Predoctoral Stages Programme of Universitary Researchers in Spanish Universities and Research Centres from the Spanish Ministry of Science and Innovation (MICINN). The authors wish to thank Mr. Manuel Planes i Insausti and Dr. Jose Luis Moya Lopez, the technical supervisors responsible for the Electron Microscopy Service at the Polytechnic University of Valencia.Domenech Carbo, MT.; Silva, MF.; Aura Castro, E.; Fuster López, L.; Kröner ., SU.; Martínez Bazán, ML.; Mas Barberà, X.... (2011). Study of behaviour on simulated daylight ageing of artists¿ acrylic and poly(vinyl acetate) paint films. Analytical and Bioanalytical Chemistry. 399:2921-2937. https://doi.org/10.1007/s00216-010-4294-3S2921293739

Revisión de la obra de Antonio Bisquert en la ciudad de Teruel a través de su análisis radiográfico y caracterización de materiales mediante SEM/EDX

The present research work, with an interdisciplinary character, focuses on a study where historical-artistic data were combined with extensive radiographic documentation and extensive stratigraphic and chemical studies using optical microscopy and scanning electron microscopy. All this on a set of eight canvases of the artistic work`s Antonio Bisquert in the city of Teruel. These works are located in the Museum of Sacred Art of Teruel and in different churches of this area. The results show a compendium of radiographic unpublished images, which reflects the entire creative process and the genesis of the works, revealing contrasted attributions and the use of subsequent retouchings considered not original, which were executed by the same hand at the same time. All these data generate a great interest for the recognition and the development of forgotten the artist’s output.O presente trabalho de pesquisa, com claro caráter interdisciplinar, enfoca um estudo em que dados histórico-artísticos foram combinados com extensa documentação radiográfica, além de um amplo estudo estratigráfico e químico utilizando microscopia ótica e microscopia eletrônica de varredura. Tudo isso num conjunto de oito telas da produção artística do pintor Antonio Bisquert na cidade de Teruel. Obras que estão localizadas tanto no Museu de Arte Sacra de Teruel, como em diferentes igrejas da mesma cidade. Tanto os resultados obtidos a partir das imagens radiográficas quanto os oferecidos pelos testes analíticos formam um compêndio sem precedentes do que se reflete em todo o processo criativo e sua gênese, revelando atribuições contrastadas e o uso de retoques subsequentes considerados não originais, que foram executados pela mesma mão ao mesmo tempo. Todos esses dados geram um grande interesse pelo reconhecimento e valorização do trabalho desse pintor esquecido.El presente trabajo de investigación, con un claro carácter interdisciplinar, se focaliza en un estudio donde se han combinado datos histórico‐artísticos junto a una extensa documentación radiográfica, más un amplio estudio estratigráfico y químico mediante Microscopía óptica y Microscopia electrónica de barrido. Todo ello sobre un conjunto de ocho lienzos de la producción artística del pintor Antonio Bisquert en la ciudad de Teruel. Las obras analizadas en este artículo se encuentran localizadas tanto en el Museo de Arte Sacro de Teruel, como en diferentes iglesias de esa misma localidad. Tanto los resultados obtenidos de las imágenes radiográficas como los que ofrecen las pruebas analíticas conforman un compendio inédito de lo que se refleja en todo el proceso creativo y su génesis, revelando atribuciones contrastadas y el empleo de posteriores retoques considerados como no originales, que fueron ejecutados por una misma mano en una misma época. Todos estos datos generan un gran interés para el reconocimiento y puesta en valor de la obra de este olvidado pintor

An evaluation of changes induced by wet cleaning treatments in the mechanical properties of paper artworks

Wet cleaning of ancient papers is a common treatment performed for the removal of degradation products, external contaminants and salts, which can promote the degradation of cellulose (i.e., hydrolysis, oxidation). In this research, the effects on the mechanical properties of paper samples caused by wet cleaning treatments were evaluated by considering the changes induced in the ultimate tensile strength, deformation at break and flexibility. For this purpose, samples were subjected to different aqueous cleaning treatments such as immersion in deionised water and the application of rigid gels of agar and gellan gum at different concentrations was carried out. Tensile tests were run, and morphological observations of paper by means of light microscopy and scanning electron microscopy were recorded. Contrary to the significant changes in the mechanical properties of paper samples after immersion treatment (an increase in flexibility as the elongation at break), the use of gelled systems caused slight improvement in the mechanical properties of paper (in both the ultimate tensile strength as well as in the breaking strain). Changes in the mechanical properties of paper were also correlated with slight changes in the diameter of the cellulose fibres as a consequence of the swelling action of water molecules, especially in the case of immersion treatment. Finally, the tensile tests performed on the paper samples after thermohygrometric accelerated artificial ageing (70 C and 65 % RH) demonstrated that cleaning treatments by rigid gels did not seem to accelerate any sort of paper degradation in the mid to long term

Análisis de un enterramiento con cubierta ›entelado‹ de época altoimperial en Augusta Emerita (Mérida, Badajoz)

Vorgestellt wird ein Grab aus der frühen römischen Kaiserzeit mit textilen Resten, die auf der Abdeckung befestigt waren. Es wurde in Augusta Emerita (heute: Mérida) gefunden. Es wurde eine archäologische und kontextuelle Untersuchung des Grabes sowie zu den gefundenen Materialien durchgeführt. Hinzu kamen auch eine Reihe von archäometrischen Analysen, die einen Einblick auf die Art des verwendeten Gewebes liefern und helfen, diese merkwürdige Technik besser zu verstehen.We present a grave dated in the Early Roman Empire times with remains of textiles adhered on its cover. It was located in Augusta Emerita (current Mérida). We carry out an archaeological and contextual study of the tomb as well as a research of the materials located in its deposit. In addition we have made a series of archaeometric analyzes that allow us to know the nature of the fabric used and to present an approach of the praxis of this curious practice.Presentamos una tumba datada en época altoimperial con restos textiles adheridos a su cubierta. Fue localizada en Augusta Emerita (actual Mérida). Realizamos un estudio arqueológico y contextual de la tumba así como de los materiales localizados en su depósito. Además, estas muestras se han sometido a una serie de análisis arqueométricos que permiten conocer la naturaleza del tejido usado y acercarnos a la praxis de esta curiosa práctica

Análisis de un enterramiento con cubierta ›entelado‹ de época altoimperial en Augusta Emerita (Mérida, Badajoz)

Vorgestellt wird ein Grab aus der frühen römischen Kaiserzeit mit textilen Resten, die auf der Abdeckung befestigt waren. Es wurde in Augusta Emerita (heute: Mérida) gefunden. Es wurde eine archäologische und kontextuelle Untersuchung des Grabes sowie zu den gefundenen Materialien durchgeführt. Hinzu kamen auch eine Reihe von archäometrischen Analysen, die einen Einblick auf die Art des verwendeten Gewebes liefern und helfen, diese merkwürdige Technik besser zu verstehen.We present a grave dated in the Early Roman Empire times with remains of textiles adhered on its cover. It was located in Augusta Emerita (current Mérida). We carry out an archaeological and contextual study of the tomb as well as a research of the materials located in its deposit. In addition we have made a series of archaeometric analyzes that allow us to know the nature of the fabric used and to present an approach of the praxis of this curious practice.Presentamos una tumba datada en época altoimperial con restos textiles adheridos a su cubierta. Fue localizada en Augusta Emerita (actual Mérida). Realizamos un estudio arqueológico y contextual de la tumba así como de los materiales localizados en su depósito. Además, estas muestras se han sometido a una serie de análisis arqueométricos que permiten conocer la naturaleza del tejido usado y acercarnos a la praxis de esta curiosa práctica