Conservation of Modern Oil Paintings

Table of Contents

1. Frontmatter

2. Chapter 1. Challenges in Research: Connecting Scientific Analysis with Conservation Practice

   Aviva Burnstock, Klaas Jan van den Berg, Judith Lee, Bronwyn Ormsby

   Abstract

   This paper discusses the need for conservators to be in a position to evaluate scientific research to inform their conservation practice. A range of methods and approaches to research in selected recent studies is highlighted together with suggestions about how the results of molecular level material studies may be used by conservators to guide more specific and appropriate treatment choices. The advantages and compromises of case study research and the use of aged reconstructions is highlighted in relation to ethical and practical criteria with evaluation of treatment options for cleaning modern oil paintings. A case study highlights the issues and an approach for treatment of a modern partly varnished oil painting with sensitive passages of paint containing epsomite.

3. Chapter 2. Evaluating Cleaning Systems for Use on Water Sensitive Modern Oil Paints: A Comparative Study

   B. Ormsby, J. Lee, I. Bonaduce, A. Lluveras-Tenorio

   Abstract

   This paper outlines the approach and key findings of systematic studies into the use of various surface cleaning materials on a range of accelerated-aged sensitive oil paint surfaces, carried out through the Cleaning Modern Oil Paints (CMOP) project. Studies involved the use of recently introduced options such as adjusted pH and conductivity waters, spreadable gels, rigid gels, silicone emulsifiers, and mineral spirits-based microemulsions, with additional explorations into the effects of application methods. The evaluation methodology encompassed star diagrams designed to capture observations made during cleaning tests, and paint surface evaluations using digital microscopy, colour and gloss assessment, and ATR-FTIR analysis. In most cases, the most promising free solvents were subsequently incorporated into spreadable and rigid gels, water-in-oil microemulsions and silicone emulsions, tailoring the approach to further minimise undesirable effects where possible. Cleaning system residues were also investigated using visual inspection, microscopy and ATR-FTIR analysis, with a selection of samples further investigated using a pyrolysis on-line micro-reaction sampler and XPS analysis. The combined results offer information on the advantages and risks associated with each cleaning material, and an approach to optimising wet systems for the cleaning of sensitive oil painted surfaces.

4. Paint Technology

   1. Frontmatter

   2. Chapter 3. Pigment Surface Treatments: 20th and 21st Century Industrial Techniques and Strategies for their Detection

      Carolina Salis Gomes, Cátia Ferreira, Brenda Rossenaar, Ineke Joosten, Inez van der Werf, Leslie Carlyle, Klaas Jan van den Berg

      Abstract

      Pigment manufacture in the twentieth and twenty-first centuries has largely been intended for industrial applications. The very small and specialised artist’s materials market relies on these industrially produced pigments. Improvements to enhance pigment performance in industry have led to the use of a variety of inorganic or organic surface treatments. Present on the surface of individual pigment particles and making up less than 10% of the total weight of pigment, the detection and identification of these materials presents a challenge. Part I of this paper summarises information from key literature sources which describe surface treatment materials, application methods and the terminology currently in use. Part II explores the analytical strategies employed to detect these treatments on pigment samples. The pigments selected for this study include: Cu-Phthalocyanine Blue and the Hansa yellows PY3 and PY74, Umber, Vine Black, synthetic Ultramarine Blue, Lead White, Zinc White, and Titanium White. Analysis of inorganic materials involved SEM-EDX; (S)TEM-EDX; and Field Emission Gun SEM. For the analysis of organic materials, Evolved Gas Analysis MS and Py-GC/MS were used.

   3. Chapter 4. Meet the Future: The Creation of New Pigments

      Matthijs de Keijzer

      Abstract

      Since the publications concerning twentieth century synthetic inorganic and organic artists’ pigments in 2011 and 2014 respectively, new, twenty-first century inorganic pigments have been discovered, patented and brought onto the market. In this article, rutile tin zinc oxide (PY 216 and PO 82), niobium tin pyrochlore (PY 227), YInMn blue (PB 86) and Vantablack are introduced. Their history, development, manufacture, properties, applications and use as artists´ pigments will be discussed. These pigments possess excellent properties and could enter the artists´ palette in the future.

   4. Chapter 5. Zinc Oxide in Oil-Based House Paint: Insights from a Paint Chemist’s Notebook Dated 1949

      Anne Carter, Gillian Osmond, Paula Dredge, Bruce Leary

      Abstract

      The Dulux Archives in Melbourne hold a set of four laboratory notebooks written by Brian Roberts while a trainee paint chemist at British Australian Lead Manufacturers (BALM) Pty. Ltd. in 1949. This paper focuses on information contained in the notebooks detailing company testing and practical tools for managing known zinc oxide reactivity in oil-based house paints. Acceptable application and weathering properties of zinc oxide in oil paint formulations emphasized good quality larger particle size zinc oxide pigment at correct pigment volume ratio, appropriate driers and importantly, the use of stand oil. The notebooks provide a prompt to consider the effect of the stand reaction on linseed oil acids and subsequent soap formation. Although stand oils can contain a high proportion of acids available for reaction with zinc ions, due to Diels-Alder reactions during the stand process a proportion have likely become cyclic. The subsequent cyclic zinc carboxylates may inhibit aggregation and crystallisation and thus may be less problematic in paint films than zinc carboxylates of the straight chain fatty acids found in untreated linseed oil – rendering zinc oxide in stand oil more stable.

   5. Chapter 6. A Glimpse into the House and Decorative Paint Market in Norway During World War I (1914–1918)

      Barbro Wedvik

      Abstract

      In the first half of the twentieth century in Norway, linseed oil was the primary binding medium used in house paint, decorative paint and artists’ paint. During the First World War (WWI), however, the cost of linseed oil rose dramatically. In 1917, it was rationed, and it then became unavailable for commercial paint use. What were the consequences of the restricted access to linseed oil? To examine this question, articles and advertising published in Maleren, a biweekly Norwegian journal for house and decorative paint, with house painters and architects as the target audience, were studied. The research results show that a range of so-called surrogate products became available in Norway during WWI. Diverse materials were used as binding media in the paint, and the quality of the available paint products varied widely. The research contributes to a broader understanding of the house painters’ market in this complex period and gives important background information for conservators examining architectural decorations as well as easel paintings which were created in Norway during WWI.

   6. Chapter 7. Approaches to the Identification of Royal Talens ETA (Emulsion) Paint in Objects of Art

      Lisanne van den Heuvel, Inez van der Werf, Coos van Waas, Klaas Jan van den Berg

      Abstract

      The Dutch manufacturer of paints and art supplies, Royal Talens, produced the casein/oil emulsion paint ‘ETA’ from 1932 until c. 1980. ETA, a rainwater resistant decoration paint, was made for in- and outdoor embellishments and commercial designs, but seems also to have become popular amongst artists after WWII. Artists appreciated the relatively cheap ETA, because of its versatility and attractive matte finish. Thanks to the RCE’s collaborative agreement with Royal Talens, information has become available on ETA’s formulations and production from the Talens archive. This research discusses possible approaches for the identification of ETA in objects of art.

      Changes in formulations over time were analysed by research into the production records and original paints. All surviving ETA recipes were assembled and entered into a database, showing many variations that may be helpful not only to identify ETA paints in works of art, but also providing a narrow range of production date possibilities. The archival information was linked with other sources such as: original colour (advertisement) charts, remnants of ETA paints from old tins and flasks and various applications of ETA paint in works of art to provide information on the chemical composition and possible appearances of ETA paints. To this end, XRF was used as a non-destructive starting point to identify elements from inorganic pigments and fillers and Py-GC/MS was adopted to obtain an overall overview of the ingredients that were used in ETA’s binding medium. Raman spectroscopy provided information on the synthetic organic pigments.

   7. Chapter 8. Synthetic Organic Pigments in Talens Oil Paint 1920–1950 – The Case of Vermillion imit

      Rika Pause, Johan G. Neevel, Klaas Jan van den Berg

      Abstract

      The Dutch paint manufacturer Talens & Co (now Royal Talens) started the production of the brand Rembrandt Olieverven in 1904 in Apeldoorn and much of the company’s historical archive still remains.

      The aim of the project “synthetic organic pigments in Talens oil paint”, to which this article refers, was to obtain information about the synthetic organic pigments used in early Talens oil paints. The production archive provided logbooks from the years 1922 to 1950, 174 Talens oil paint tubes and 10 Talens oil paint charts. Archival research on the production of these oil paints was complemented by analysis of historical paint tubes. This article will present the representative investigation of the Talens oil paint Vermilion imit. to explain the applied methodology as a case study.