FALL 2016
Unlikely Synergies
How Paints Formulated for Military Assets May Save Outdoor Painted Sculptures
By Abigail Mack, John Escarsega, and Rachel Rivenc

As an extension of the groundbreaking abstract art movement of the early twentieth century, many artists in the second half of the century felt the need to create artwork that could be displayed outside of traditional gallery and museum spaces. Although the creation of outdoor memorials to war heroes and prominent public figures was well established historically, modern artists sought to engage in a different type of dialogue with the public in cityscapes and landscapes. This new conversation included abstract or abstracted subject matter and sharply departed from traditional outdoor materials, especially by embracing modern and painted metals. Now, half a century after modern art was placed outdoors, many sculptures require major treatment, and conservators are developing strategies for their long-term preservation.

Modern metals—such as aluminum, stainless steel, Cor-Ten, and structural steel—have distinct advantages for outdoor display by providing strength plus relative lightness, permitting spectacular architecture and artworks. Numerous artists chose to paint the industrial materials, both furthering aesthetic expression and providing important protection to the underlying metal. However, outdoor painted sculpture has turned out to require extensive maintenance and frequent conservation. No paint, whether for an automobile, water tower, or sculpture, will maintain its appearance indefinitely in an outdoor environment. Once the protective paint layer is breached, the metal substrate is vulnerable, often leading to rapid deterioration. Repainting, although not acceptable for indoor works of art, is a regular practice with outdoor painted sculpture, since these objects were made by fabricators, finished by industrial painters, and intentionally placed in environments where change is inevitable.

For the last thirty to fifty years, these sculptures have been on a continuous cycle of painting and repainting, both for preservation and in an attempt to maintain their intended appearance. Treatments often are massive logistical and financial endeavors that strain collectors and institutions. Because of additional factors including economic changes and shifting priorities, visitors to cityscapes and sculpture gardens have often only briefly witnessed newly painted objects as intended, before the artworks declined into years of visual disfigurement. Furthermore, paints were then chosen to best replicate the intended look of the object; as paint formulations changed and companies closed or transferred ownership, other paints were identified without established methods of ensuring aesthetic continuity. It is not always clear that current paints accurately represent artist intentions. Moreover, it has often been the practice to choose a more glossy paint than the original gloss level, with the expectation that it would then fade and chalk with weathering to the accepted level.

A Different Conservation Approach

Just as the artists of these modern monuments embarked upon new ground, conservators must take a different approach that focuses on maintaining the artist’s “intended appearance” in contrast to traditional conservation ethics of preserving original materials and emphasizing reversibility and minimal intervention. The conservation focus shifts from preservation of the physical coatings to preservation of the artist’s original intent for appearance, with the additional requirement of effective protection of the substrate. For this approach, the challenge is balancing a solid working knowledge of industrial outdoor coating systems with conservation guidelines for practice, which include sensitivity to the appearance the artist intended for the work.

Within the already difficult category of painted outdoor sculpture, matte (or low gloss) coatings are the most problematic in terms of durability. They are, however, ubiquitous, especially with sculptures from the 1960s, 1970s, and 1980s, when many artists favored a low gloss aesthetic. The poor durability of matte commercial coatings in outdoor settings is well known. They are unavoidably overloaded with pigments and flattening agents, and they contain a minimal amount of resin. These factors, often exacerbated by poor choices of these pigments and flattening agents, typically lead to fading, streaking, marring, and degrading with each passing season until sculpture surfaces no longer resemble the original unexposed coating and fall far from the artist’s intended look. In some climates, severe weathering and subsequent disfiguration have been documented to occur in less than three years.

Although at first glance the worlds of the military and of art conservation could not seem further apart, they share a common reliance on matte coatings—with different but equally stringent requirements. For the military, concealment and camouflage necessitate matte coatings, while in the art world appearance is dictated by aesthetic choice and is therefore essentially nonnegotiable. In 2001 efforts at the National Gallery of Art in Washington, DC, to identify durable high-performance matte coatings designed for an outdoor environment led to an unlikely alliance between the US Army Research Laboratory (ARL) and art conservation professionals. As a result of this collaboration, existing military camouflage paint formulations were adapted for outdoor sculpture by Alexander Calder and Tony Smith. The results were extremely promising, although problems with the application properties of the paint were reported, arising in part from the very different working methods used by the Army and by conservators and local paint applicators. Recent coatings technology requires the implementation of sophisticated pretreatment steps and stringent industry surface preparation standards. The art conservation community is often still unaware of the additional steps used in industry or is generally reluctant to prepare sculpture surfaces to industry standards (using methods such as abrasive blasting) that have been proven to be necessary for good adhesion. The fact that some of these methods simply cannot be employed to the same degree with works of art is thought to have been the cause of some premature failures, and these problems highlight the need for further interprofessional collaboration.

The Outdoor Sculpture Project

In recognition of the fact that outdoor painted sculptures are a very significant part of our modern artistic heritage that pose major conservation issues, the Getty Conservation Institute (GCI) in 2012 launched a project focused on their preservation. An initial experts meeting that year, organized by the GCI and hosted by the Metropolitan Museum of Art in New York, gathered a multidisciplinary group of professionals including conservators, scientists, curators, artists and artists’ estates, paint manufacturers, fabricators, and industrial painters to discuss challenges and to help define a path forward. As a result of the meeting, a number of potential solutions to those challenges were suggested, one of which was to build bridges between the industrial paint world and the art world. An important component of this effort has been to partner with the ARL coating team to promote the formulation of a new generation of outdoor coatings with enhanced performance: the Marathon Series. Another essential aspect is to work with artists, artists’ estates, and foundations to replicate the approved appearance of their artists’ sculptures using this novel coating technology.

The ARL formulated these new paints with the express goal of increasing their durability and ease of application. The formulations include two critical innovations: one is the use of lower molecular weight resin systems, which decreases the amount of solvent needed and lowers viscosity, thus resulting in enhanced application properties. The other important technical advance is the use of Low Solar Absorbing (LSA) pigments, which contributes to effectively reducing solar loading—i.e., reflecting the sun’s thermal energy and photons—not only reducing the heating of the coating and the underlying substrate, but also protecting the resin from harmful degradation of the coatings that occurs through ultraviolet exposure. Currently, because of the limited color choices of LSA pigments, the new paints have been formulated only in black, and a variety of different gloss levels are being explored to fit the different aesthetic requirements of artists including Louise Nevelson, Tony Smith, and Alexander Calder.

Maria Nevelson and Joyce Pomeroy Schwartz evaluating different black paint samples

The artists’ choice of color and gloss was crucial to their intended visual impact. Even black is not a simple color—rather, it has important subtleties and differences. Louise Nevelson described her choice of color in no uncertain terms: “Black is the most aristocratic color of all. There is no color that will give you the feeling of totality. Of peace. Of greatness. Of quietness. Of excitement. I have seen things that were transformed into black, that took on just greatness. I don’t know a lesser word.”1 The black has been described by the Louise Nevelson Foundation as very matte and very jet-black with no reflection.2 Tony Smith described his objects as “voids” and said of them, “they are black and probably malignant.”3 The Tony Smith Estate defined the intended appearance of the black he used as a “dull semi-gloss”4 and emphasized that for Smith the hue of the black (e.g., cool or warm) was not as critical as the gloss level. Alexander Calder consistently specified low gloss coatings for both his indoor and his outdoor sculptures and referred to his outdoor sculptures as his “dreadnoughts,” after the imposing class of battleships from the early twentieth century.5 Beyond just his personal preference, the Calder Foundation has described the artist’s interest as seeing the form of the sculpture rather than being distracted by a surface reflection.6

Having input from artists’ estates, foundations, and studios, as well as from conservators and paint applicators, in the early stages while paint formulation is being developed is a unique opportunity. It means not only that appearances can be tailored, but also that other properties, such as viscosity and drying time, can be adjusted. The next step will be large-scale tests for paint applicators, followed by pilot applications to select sculptures, in collaboration with the relevant foundations and estates. The commercial availability of these paints will be ensured through partnerships among the GCI, the ARL, and commercial paint manufacturers with a long history of collaboration with the ARL. In the long term, the goal is to expand the color and gloss palette available to fit the requirements of other artists. This goal will be achieved by introducing different pigment packages into the new resin system and, crucially, working with an increasing number of artists’ estates, foundations, and studios to provide feedback as the paints are being individually formulated to match their specified appearance. Ultimately, the hope is that more durable coatings will help sculptures maintain their appearance longer and ensure that the dialogue between the sculpture and the spectator continues.

Abigail Mack, an independent conservator, and John Escarsega, who is with the Army Research Laboratory, are team members of the GCI's Outdoor Sculpture project. Rachel Rivenc is a GCI associate scientist and the project's leader.

1. Louise Nevelson, Dawns and Dusks: Taped Conversations with Diana MacKown (New York: Charles Scribner’s Sons, 1976), 126.
2. 2016 conversation with Maria Nevelson and Arne Glimcher regarding the parameters for appearance of Louise Nevelson’s black sculptures.
3. Samuel J. Wagstaff, ed., Tony Smith, Two Exhibitions of Sculpture, exhibition catalogue (Hartford, Connecticut: The Atheneum, and Philadelphia: The Institute, 1966).
4. 2001 conversation with Sarah Auld, director of the Tony Smith Estate, regarding parameters for the appearance of Tony Smith’s outdoor black sculptures.
5. “The Adventures of Sandy Calder,” Kansas City Star, November 20, 1966.
6. 2015 conversation with Alexander S.C. Rower regarding the surface appearance of sculpture by Alexander Calder.