Artists working in the post-WWI era frequently used industrial products in their work. This can put conservators in the position of dealing with materials with unknown compositions and behaviors that are not conducive to long-term preservation. Unfortunately, existing conservation literature does not always provide adequate materials information or case studies for conservators wrestling with these issues. Expanding literature searches to include period industrial articles can fill in those informational gaps.
Dawn Rogala discovered the benefits of such industrial literature while researching mid-century American oil-based zinc oxide house paint during her postgraduate fellowship at the Smithsonian Institution in Washington, DC. Her research focused on a group of abstract expressionist paintings and the relationship between their zinc oxide grounds and failure of the paint layers. She found that industrial literature provided significant evidence of a connection between the choice of materials and the current unstable condition of the paintings.
The period between 1925 to 1950 provided Rogala with the most useful articles, likely due to market demand and frequent product adaptation during that time. The largest percentage of articles she found were presented by representatives of the paint manufacturers who were focused on promoting the benefits of their paint to consumers. Those may seem like biased and unreliable sources for accurate information, however such articles often mentioned engineered mechanical behaviors that were considered beneficial in their paint films. Approximately 25% of the articles in her research were affiliated with scholarly research. Those articles provided more comprehensive and practical analyses of paint film behaviors with useful reference bibliographies.
Weathering test articles were another rich source of information on paint formulations and behaviors. The variations in regional weather often caused adaptations in regional paint formulations. This meant that artists working with a zinc oxide house paint in a mild climate may have worked with an entirely different formulation of zinc oxide house paint than an artist working in a more severe climate during the same period. It also suggested titanium dioxide’s introduction into house paints in the mid-1950s could have been delayed on a global scale when considering issues of climate influences on formulation changes.
One of the specific examples Rogala gave to illustrate the usefulness of industrial literature referred to self-renewing paint films. Weathering test articles cited a preference for acicular particles because their brittle nature allowed for microfissures in the paint, which would cause it to slough off in the rain and result in a crisp clean surface. Another example was the mention that three years was the required life expectancy for engineered paint films according to industrial standards. While such qualities were acceptable and even desirable in house paints, such paint films pose clear disadvantages for conservation. In fact, Rogala pointed out a 1909 article that warned about the dangers of zinc oxide paint as a ground layer!
I thought this was an outstanding presentation. Conservators must be resourceful and adaptable when dealing with unknown, unpredictable materials. This is a particular necessity when it comes to the conservation and preservation of modern and contemporary artwork. I appreciate Rogala’s study for delving into the industrial side of zinc oxide and providing an open look at a somewhat unconventional resource for conservation research.