Katrien Keune

Katrien Keune
Rijksmuseum Amsterdam · Science

About

97
Publications
52,562
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
1,819
Citations
Citations since 2016
62 Research Items
1402 Citations
2016201720182019202020212022050100150200250
2016201720182019202020212022050100150200250
2016201720182019202020212022050100150200250
2016201720182019202020212022050100150200250

Publications

Publications (97)
Chapter
Full-text available
Oil paint is a dynamic system that undergoes chemical alteration on several time and length scales. At the short term, curing reactions are necessary for oil to dry properly. At longer time scales, a wide variety of other chemical processes can negatively affect the visual appearance or mechanical properties of historical artistic paint systems. Th...
Article
Full-text available
Over time, artist pigments are prone to degradation, which can decrease the readability of the artwork or notably change the artist's intention. In this article, the visual implication of secondary degradation products in a degraded yellow rose in a still life painting by A. Mignon is discussed as a case study. A multimodal combination of chemical...
Article
Full-text available
Over time, artist pigments are prone to degradation, which can decrease the readability of the artwork or notably change the artist's intention. In this article, the visual implication of secondary degradation products in a degraded yellow rose in a still life painting by A. Mignon is discussed as a case study. A multimodal combination of chemical...
Article
This study investigates how lead isotopes in lead white pigment can be used as an additional diagnostic tool to constrain the production time of 17th century Dutch paintings. Analysis of 77 well-dated paintings from 27 different Dutch artists reveal significant change in the source of lead used in lead white at the start, middle, and end of the 17t...
Article
Full-text available
Evolon $$^\circledR$$ ® CR is increasingly used in paintings conservation for varnish removal from oil paintings. Its key benefits over traditional cotton swabs are limiting solvent exposure and reducing mechanical action on the paint surface. However, this non-woven microfilament textile was not originally engineered for conservation use and littl...
Article
Full-text available
X-ray absorption and optical luminescence can both provide valuable but very different information on the chemical and physical properties of materials. Although it is known that the spectral characteristics of many materials are highly heterogeneous on the micro- and/or nanoscale, no methodology has so far been shown to be capable of spatially res...
Article
Full-text available
Visible and infrared reflectance imaging spectroscopy is one of the several non-invasive techniques used during Operation Night Watch for the study of Rembrandt’s iconic masterpiece The Night Watch (1642). The goals of this project include the identification and mapping of the artists’ materials, providing information about the painting technique u...
Article
Full-text available
The crystallization of metal soaps in oil paint is an important chemical phenomenon that affects the appearance and structural stability of many works of art. A deep understanding of the structural transitions that occur during crystallization and their kinetics will help to support conservation decisions that minimize future detrimental change to...
Article
Full-text available
While the chemistry of artists’ paints has previously been studied and reviewed, these studies only capture a portion of the properties affecting the response of paint materials. The mechanical properties of artists’ paints relate to the deformation response of these materials when a stress is applied. This response is dependent on many factors, su...
Article
Full-text available
X-ray linear dichroism (XLD) is a fundamental property of many ordered materials that can for instance provide information on the origin of magnetic properties and the existence of differently ordered domains. Conventionally, measurements of XLD are performed on single crystals, crystalline thin films, or highly ordered nanostructure arrays. Here,...
Article
Full-text available
The autoxidation of triglyceride (or triacylglycerol, TAG) is a poorly understood complex system. It is known from mass spectrometry measurements that, although initiated by a single molecule, this system involves an abundance of intermediate species and a complex network of reactions. For this reason, the attribution of the mass peaks to exact mol...
Article
Full-text available
Oil paint binding media are complex polymer networks that harbor populations of metal ions. Understanding of the reactivity of these metal ions, often closely linked to paint degradation, is crucial to support paintings conservation efforts. By developing a spectrum fitting approach for the analysis of Fourier transform infrared spectra, we have st...
Article
The heterogeneity of lead isotope ratios of lead white paints within individual paintings is evaluated. The analyses of five different 17th-century Dutch paintings, sampled in different locations, identifies the presence of isotopic heterogeneity in lead white within a single painting. Pure pigment in the form of cones of 16th-century Venetian lead...
Article
Full-text available
An unusual phenomenon occurred in new display cases at the Rijksmuseum four months after their installation in April 2013. White deposits were visible on glass windows, silicone door gaskets, black structural adhesive seals, and on works of art. The works of art most affected by these deposits were bronze sculptures, wooden and waxed objects, tempe...
Article
Full-text available
The in-situ formation of lead-sulfur inorganic compounds in historical oil paintings can have a strong detrimental effect on an artwork’s physical and visual integrity. In this paper, paint micro-samples collected from several paintings from the Rijksmuseum (Amsterdam) and Mauritshuis (The Hague) collections were probed at the micro-scale using a c...
Article
Full-text available
Metal soap formation is one of the most wide-spread degradation mechanisms observed in historical oil paintings, affecting works of art from museum collections worldwide. Metal soaps develop from a chemical reaction between metal ions present in the pigments and saturated fatty acids, which are released by the oil binder. The presence of large meta...
Article
Full-text available
The exposure of oil paintings to organic solvents for varnish removal or to water for the removal of surface dirt can affect the chemical and physical properties of oil paint in an undesired way. Solvents can temporarily plasticise and swell the polymerised oil paint binding medium, enhancing both the thermal mobility and mechanical displacement of...
Article
Full-text available
Besides its many applications in electronics, photonics, and catalysis, ZnO has also been extensively used as the pigment zinc white ever since its introduction in the first half of the 19th century. It is shown here that zinc whites (ZnO formed through zinc vapor oxidation) form a chemically binary system, with each of the submicrometric crystalli...
Article
Full-text available
Abstract The science of oil paint cleaning is an interdisciplinary and challenging field of study due to the complex nature of both paintings and cleaning materials. The topic requires an intimate and iterative collaboration between conservation scientists and paintings conservators. In such an interdisciplinary field, it can sometimes be difficult...
Article
Full-text available
Ultramarine blue pigment, one of the most valued natural artist’s pigments, historically was prepared from lapis lazuli rock following various treatments; however, little is understood about why or how to distinguish such a posteriori on paintings. X-ray absorption near-edge structure spectroscopy at the sulfur K-edge in microbeam and full-field mo...
Article
Ultramarine blue paint layers in oil paintings can be affected by ultramarine ‘disease’ or ‘sickness’: a phenomenon described by a grey appearance and a loss of detail in the artwork. An explanation for this phenomenon is an interaction between the organic binder network and ultramarine pigment, with the pigment acting as a catalyst for the breakdo...
Article
Full-text available
A micro‐invasive technique is presented that enables pigment sampling from individual layers of a painting cross section by obtaining a furrow 10‐50 μm wide of chosen length. Combined with increased sensitivity of lead isotope analysis using MC‐ICPMS equipped with a 1013 Ω resistor or a Pb double spike technique, the amount of Pb needed for isotopi...
Article
Full-text available
Johannes Vermeer (1632–1675) is known for his brilliant blue colours, and his frequent use of the costly natural ultramarine. This paper reveals new findings about ultramarine in the headscarf of Girl with a Pearl Earring (c. 1665, Mauritshuis). The painting was examined using a range of micro- and macroscale techniques as part of the Girl in the S...
Article
Full-text available
Although the concentration of carboxylic acid (COOH) groups is crucial to understand oil paint chemistry, analytical challenges hindered COOH quantification in complex polymerised oil samples thus far. The concentration of COOH groups is important in understanding oil paint degradation because it drives the breakdown of reactive inorganic pigments...
Article
Zinc oxide (ZnO) is a II-VI semiconductor that has been used for the last 150 years as an artists’ pigment under the name of zinc white. Oil paints containing zinc white are known to be prone to the formation of zinc carboxylates which can cause protrusions and mechanical failure. In this paper, it is demonstrated how a multispectral synchrotron-ba...
Article
Full-text available
Abstract The spontaneous chemical alteration of artists’ pigment materials may be caused by several degradation processes. Some of these are well known while others are still in need of more detailed investigation and documentation. These changes often become apparent as color modifications, either caused by a change in the oxidation state in the o...
Article
Full-text available
The molecular structure around metal ions in polymer materials has puzzled researchers for decades. This question has acquired new relevance with the discovery that aged oil paint binders can adopt an ionomer structure when metal ions leached from pigments bind to carboxylate groups on the polymerized oil network. The characteristics of the metal-p...
Article
Full-text available
The impact of solvent exposure on oil paintings and the differences between solvent application methods are longstanding topics in cleaning studies. Solvent exposure is ideally kept to a minimum, because solvent swelling can lead to the extraction and displacement of reactive paint components. In particular, important concerns are fatty acids displ...
Chapter
An overview is presented of the current state of understanding of the chemical pathways that lead to the formation of crystalline metal soap phases in oil paints, based on recent experimental work by the authors and supported by relevant literature. Improved (quantitative) interpretation of Fourier-transform infrared (FTIR) spectra has revealed tha...
Chapter
Full-text available
This paper describes a photoluminescence imaging approach coupled to a synchrotron source (SR-PL imaging) that provides a new, powerful way to probe the processes involved in metal soap formation in paint films, processes that play an important role in the deterioration of paint films in traditional and modern oil paintings.
Chapter
Full-text available
The Evolution triptych by Piet Mondrian (1911, oil on canvas, Gemeentemuseum Den Haag) presents a case study of a painting that is seriously affected by zinc soap formation, which has resulted in paint delamination and paint loss, particularly in the cadmium yellow paint areas. The paint is extremely fragile, which makes the paintings vulnerable wi...
Chapter
The painted wall hanging (Andries Warmoes, signed and dated 1778) in the rear salon of the eighteenth-century Hofkeshuis in Almelo, Netherlands, offers a unique opportunity to study the relationship between lead soap formation and age craquelure in the oil paint on these canvasses. The proportion of intact lead white pigments to lead soap-rich area...
Cover Page
Full-text available
Rembrandt is renowned for his impasto, a paint with outstanding rheological properties, the exact formulation of which has remained a mystery. In their Communication (DOI: 10.1002/anie.201813105), V. Gonzalez et al. used synchrotron X-ray diffraction to investigate microscopic samples from Rembrandt masterpieces; a rare lead compound, plumbonacrite...
Article
Rembrandt ist bekannt für seine Impasto, eine Farbe mit hervorragenden rheologischen Eigenschaften, deren genaue Formulierung ein Rätsel geblieben ist. V. Gonzalez et al. beschreiben in ihrer Zuschrift (DOI: 10.1002/ange.201813105) die Verwendung von Synchrotron‐Röntgenbeugung zur Analyse mikroskopischer Proben von Rembrandt‐Gemälden; eine seltene...
Article
Rembrandt is renowned for his impasto, a paint with outstanding rheological properties, the exact formulation of which has remained a mystery. In their Communication (DOI: 10.1002/anie.201813105), V. Gonzalez et al. used synchrotron X‐ray diffraction to investigate microscopic samples from Rembrandt masterpieces; a rare lead compound, plumbonacrite...
Conference Paper
The privately owned oil painting Composition with Color Planes 4 (1917) by Piet Mondrian (1872–1944) has been the subject of ongoing investigation since 2011. The painting consists of color planes in a field of differing whites. Some of these white areas suffer from delamination issues, in combination with flaking. Previous research demonstrated a...
Book
This go-to reference work surveys the current state of knowledge in the field of metal soap-related degradation phenomena in art works. It contains detailed descriptions and images of the different phenomena and addresses the practical aspects of soap formation, preventive conservation, and treatment. The occurrence of metal soaps is one of the def...
Article
Full-text available
The surface of many Old Master paintings has been affected by the appearance of whitish lead-rich deposits, which are often difficult to fully characterise, thereby hindering conservation. A paint micro-sample from Rembrandt's Homer was imaged using X-ray Diffraction Computed Tomography (XRD-CT) in order to understand the evolving solid-state Pb ch...
Article
Rembrandt (1606‐1669) is renowned for his impasto technique, involving his use of lead white paint with outstanding rheological properties offering some 3D modeling possibilities. This was obtained by combining lead white pigment (a mixture of cerussite PbCO3, and hydrocerussite Pb3(CO3)2(OH)2) with an organic binding medium, but the exact formulat...
Article
Rembrandt (1606‐1669) is renowned for his impasto technique, involving his use of lead white paint with outstanding rheological properties offering some 3D modeling possibilities. This was obtained by combining lead white pigment (a mixture of cerussite PbCO3, and hydrocerussite Pb3(CO3)2(OH)2) with an organic binding medium, but the exact formulat...
Chapter
Bart van der Leck, as a member and co-founder of the artistic movement De Stijl, is well-known for his abstract color plane compositions, set on extensive white backgrounds. The white background in The Woodcutters (1928, oil on canvas), which comprises the brightly luminescing semiconductor pigment zinc white, was noticed to exhibit unusual lumines...
Article
Full-text available
This article focuses on the conservation history and recent treatment (2016-2018) of the newly acquired pendant portraits of Marten Soolmans and Oopjen Coppit painted by Rembrandt in 1634. Much new information is brought to light about the nineteen-fifties treatments by William Suhr in New York and Henricus Hubertus Mertens in Amsterdam, particular...
Article
Full-text available
In the restoration of paintings, solvent diffusion and swelling of polymeric oil paint binding media are important factors to consider. Common cleaning methods with organic solvents or aqueous solutions could lead to undesirable physicochemical changes in the paint in the long term, though the extent of this effect is not yet clear. We used tailore...
Article
Full-text available
Microspectroscopic Investigation of Metal Soaps in Oil Paintings--a Case Study on late 19th Century Cobalt Green ((CoxZn1-xO) Paint - Volume 24 Supplement - Xiao Ma, Selwin Hageraats, Victoria Beltran, Mathieu Thoury, Matthieu Refregiers, Katrien Keune, Barbara H. Berrie
Article
Full-text available
Using the recently developed techniques of electron tomography, we have explored the first stages of disfiguring formation of zinc soaps in modern oil paintings. The formation of complexes of zinc ions with fatty acids in paint layers is a major threat to the stability and appearance of many late 19th and early 20th century oil paintings. Moreover,...
Article
Full-text available
The formation of metal soaps (metal complexes of saturated fatty acids) is a serious problem affecting the appearance and structural integrity of many oil paintings. We used tailored model systems for aged oil paint and time-dependent attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy to study the diffusion of palmitic a...
Article
Full-text available
The formation of metal soaps (metal complexes of saturated fatty acids) is a serious problem affecting the appearance and structural integrity of many oil paintings. We used tailored model systems for aged oil paint and time-dependent attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy to study the diffusion of palmitic a...
Article
Full-text available
Infrared spectra of samples from oil paintings often show metal carboxylate bands that are broader and shifted compared to those of crystalline metal soap standards (metal complexes of long-chain saturated fatty acids). Using quantitative attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), it is demonstrated that the bro...
Article
Full-text available
Yellow orpiment (As2S3) and red–orange realgar (As4S4) photo-degrade and the nineteenth-century pigment emerald green (Cu(C2H3O2)2·3Cu(AsO2)2) degrades into arsenic oxides. Because of their solubility in water, arsenic oxides readily migrate and are found throughout the multi-layered paint system. The widespread arsenic migration has consequences f...