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Conserving the Bwana Devil Poster

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This is a guest post authored by Conservation Technician, Anna Zastrow.

The Bwana Devil movie poster is part of the Archibald Oboler Collection in the Motion, Broadcasting, and Recorded Sound Division. The poster was severely damaged, but due to the presence of early fluorescent colorant and the significance of the Bwana Devil, it was decided the poster should be treated by the Conservation Division.

Beyond its bold design and bright colors, this Swedish movie poster marks the early use of two technologies we take for granted today. The poster was used to advertise the Bwana Devil, a film which debuted in the early 1950s. Bwana Devil was the first color, full-length film that used 3-dimensional technology. In addition to the technological significance of the movie, the poster was created using early fluorescent colorant applied in a wash before the black and yellow ink which was screen printed overtop. Under UV light the movie’s title and 3- dimensional status fluoresce bright orange. Unfortunately, prior to its acquisition by the Library of Congress’ Motion, Broadcasting, and Recorded Sound Division, the poster was damaged. It was discolored, weak, torn, and showed signs of the presence of insects. The poster was quickly taken to the conservation division where it was treated by a conservation technician with the supervision of a senior paper conservator.

Bwana Devil poster, After treatment, Under UV
Bwana Devil poster, After treatment, Under UV. Sept. 18, 2019, Conservation Division.

Before we were able to address the tears and other condition issues the poster had to undergo gentle surface cleaning to remove mold spores and insect remnants. We did this under a HEPA-filtered ventilation hood with a combination of gentle dry brushes, soft sponges, and vacuuming at low suction with a micro tool through screens. After surface cleaning, we tested the fluorescent wash and printing inks for solubility to determine if they were sensitive to water or any other solvents. If sensitive, introducing moisture could damage the appearance and stability of the poster media creating issues such as causing the color to bleed or sink! Luckily for us, the poster showed no major sensitivity.

Our biggest priority was to stabilize the ink, which was flaking off and cracked in many areas. To do this, we tested a variety of consolidants to find one that would re-adhere flakes in areas where they were lifting without adding a sheen to the matte ink.  Once selected, we spray-applied the consolidant over the surface several times, allowing time to dry between each application.

Bwana Devil poster, Consolidation of ink via airbrush
Bwana Devil poster, Consolidation of ink via airbrush. Aug. 22, 2019, Conservation Division.

Once the ink was stabilized, we started the process of humidification to relax the paper through a gradual and controlled introduction of moisture. Humidification is done by creating a chamber with a humid environment and placing the poster inside. During humidification the poster was supported over a small layer of water in a tray covered by clear acrylic sheeting. It was checked frequently to ensure that no droplets of water formed that could fall on the surface of poster. The humidity allows the paper fibers to relax and prepares it for the introduction of a larger amount of water.

Due to the fragility of the paper and ink, we blotter washed the poster by placing it on a sheet of absorbent paper (blotter) that has been thoroughly wetted. Through capillary action, dirt and discoloration from the poster were pulled into the blotter paper below. After washing, we applied another round of consolidant to further stabilize the ink. We then placed the poster under light weight between absorbent felts to encourage the poster to remain flat as it dried. After confirming the ink remained stable, we humidified the poster again to prepare it for lining.

Lining is a process that involves adhering a compatible quality paper support, in this case Japanese tissue, to the back of the original paper to reinforce and stabilize it for future handling. Before lining, we mended all tears and strengthened weak areas in the poster with thin strips of Japanese tissue. After lining, we allowed the poster to dry under tension.

When dry, we toned paper to fill losses (holes) in the poster paper. We selected a paper with a thickness and surface similar to the poster and toned it with watercolors and acrylic paints, to match the color of the paper or ink surrounding the paper loss. Matching the fluorescent color proved especially difficult with readymade commercial products so we created our own fluorescent acrylic paint from dry fluorescent pigment and an acrylic binder. After toning the fill paper, we cut pieces to match exactly the shape of the paper losses and adhered them in place.

Repair detail, Bwana Devil poster, Consolidation of ink via airbrush
Bwana Devil poster, Detail of pink and black fill. Sept. 18, 2019, Conservation Division.

With treatment complete, the poster was returned to the Motion Picture, Broadcasting, and Recorded Sound Division ready to share with future researchers and the public!

Further Resources:

Archibald Oboler Collection Finding Aid, Motion Broadcasting and Recorded Sound Division


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