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The Making of Wallpaper

Conservation and
the Huard Collection:
Preserving the Processes
of Making

Written by Brianna Turner

The collection of decorative arts and design at the RISD Museum includes not only wallpaper from the illustrious Charles and Frances Wilson Huard Collection, but also works that demonstrate their process of design, including printing blocks, drawings, and oil transparencies.

1 → The ideal temperature is 55 to 75 degrees Fahrenheit, and the ideal relative humidity is 30 to 55 percent. “Preventing and Responding to Mold in Book and Paper Collections,” Webinar through Northeast Document Conservation Center, August 8, 2023.

2 → “Code of Ethics,” American Institute for Conservation, https://www.culturalheritage.org/about-conservation/code-of-ethics.

3 → “Agents of Deterioration,” Canadian Conservation Institute, https://www.canada.ca/en/conservation-institute/services/agents-deterioration.html.

Having multiple components of this process in a collection is unique, and it allows us to learn more about the production of wallpaper, see instances of the artisans’ hands, and visualize the history and life cycles of these works. To preserve the Huard Collection, we have to understand how to care for the materials that the artists and craftspeople used. Each material has specific requirements to preserve its structural integrity, and in turn to maintain that object’s intangible cultural heritage. Overall, the best way to do this is to house works in a storage environment that is clean and temperature and humidity controlled.1 This preventative maintenance is considered the best practice for works on paper. 

In conserving an object, our first and foremost guiding principle is that we do no harm as we mitigate potential damage.2 Specifically, we try to prevent the agents of deterioration. While we cannot always stop the decay of materials, we can slow down the process of decomposition, which happens by way of physical force (abrasions, scratches, etc.), pests, pollutants, high temperature and humidity levels, exposure to light, neglect, and inherent vice.3 In addition to recognizing these agents, we offer treatments that are reversible and compatible with the objects’ characteristics.

French
Design for a Wallpaper Border, ca. 1805
Gouache and graphite on paper
32.7 x 36.5 cm (12 7/8 x 14 3/8 in.)
Mary B. Jackson Fund 34.1129

4 → Rutherford Gettens and George Stout, Painting Materials: A Short Encyclopedia (New York: Dover Publications, 1966), 16.

5 → Emily Banas, during a tour with conservators from Studio TKM Associates, RISD Museum, August 26, 2023.

One of the first steps French wallpaper designers employed was the creation of design drawings. Artists rendered their initial ideas in graphite. Graphite is made up of pure carbon bound by clay and fired at a high temperature.4 This mineral has a layered structure and is slick and light, which makes it sensitive to abrasion and smudging. Artists would then sometimes add color by applying opaque watercolor, watercolor, gouache, or tempera to the paper. By using color in their design drawings, the artists were able to experiment with various colorways, shading, and levels of opacity.5 

As for the design drawings that utilize color, opaque watercolor, watercolor, and tempera paints are each made up of different materials, contributing to their differences in opacity and textures. Knowing their vulnerabilities helps us understand how long pieces containing these materials can be exhibited and exposed to light without doing too much damage. Each type of paint uses pigments mixed in a medium, which aids in flow and helps adhere the colors to the support, or the material on which the paint sits—in this case paper.

↱ The deterioration of the paper surface is evident under magnification.

French
Flowers and Garlands Wallpaper, ca. 1780–1790
Woodblock print on paper
65.4 x 45.7 cm (25 3/4 x 18 in.)
Mary B. Jackson Fund 34.940
French
Design for Wallpaper Border, 1830
Gouache and graphite on paper
33.3 x 41.9 cm (13 1/8 x 16 1/2 in.)
Mary B. Jackson Fund 34.1173

6 → Antonella Fuga, Artists’ Techniques and Materials (Los Angeles: Getty Publications, 2006).

To make watercolors, pigments are mixed in water and fixed to the support, often aided by gum arabic.6 After drying, watercolor paint can be translucent. The organic pigments in watercolors are very light sensitive; to preserve a work’s longevity, it is important to make sure that it is either framed or in a case with a UV-filtering acrylic glazing to mitigate light damage. 

Opaque watercolor is made by mixing pigments in water and adding chalk. The addition of white to the pigments increases the opacity of the colors.
French
Design for Wallpaper, 1830
Tempera and graphite on paper
42.9 x 18.3 cm (16 7/8 x 7 3/16 in.)
Mary B. Jackson Fund 34.1174

7 → Max Doerner, The Materials of the Artist and Their Use in Painting (Harcourt Brace Janovich, 1962).

8 → Fuga, Artists’ Techniques and Materials.

9 & 10 → Doerner, The Materials of the Artist.

Traditional tempera paint is made by thoroughly mixing pigments with water (or an emulsion of water and oil) and a binder.7 Oftentimes the binder for traditional tempera paint is protein based, taking the form of egg yolk or milk.8 Although tempera can contain oil, it dries quickly as the water content evaporates. This makes trying different colors and values in a drawing a relatively fast process, which would have been important to the design artists.9 Traditional tempera paint is not without its challenges though; if the paint contains too much fat and oil, the colors can darken, discolor, and crack.10
French
Design Drawing for Wallpaper, 1840
Graphite and gouache on tracing paper
39.4 x 29.4 cm (15 1/2 x 11 9/16 in.)
Mary B. Jackson Fund 34.1180
After the designer experimented and found an acceptable pattern, narrative, or scene, artisans transferred the design to transparent paper. With the aid of chalk and a steady hand, they then transposed the design onto the wooden block.
French
Design for Ornament, ca. 1780
Tempera on oiled paper
24.8 x 22.1 cm (9 3/4 x 8 11/16 in.)
Mary B. Jackson Fund 34.1102

11 → Claude Laroque, “History and Analysis of Transparent Papers,” The Paper Conservator 20, no. 1 (20024): 17–32. DOI: 10.1080/03094227.2004.9638639.

Before transparent paper, artisans used oiled parchment paper to transfer the design. The process of oiling the parchment was accomplished in numerous ways, including submerging parchment in oil and hammering it to bond the oil to the fibers.11
French
Woodblock for Wallpaper, late 1700s
80.6 x 71.8 cm (31 3/4 x 28 1/4 inches)
Mary B. Jackson Fund 41.097

12 → Roger Rowell, ed., The Chemistry of Solid Wood (Washington, D.C.: American Chemical Society, 1984).

After transferring the design onto the prepared woodblock, an artist would hand carve the design by following the chalk lines. Each color in a design is printed from its own block, thus each wallpaper has multiple woodblocks associated with it. 

Wood is a porous material made up of organic polymers.12 Depending on the type of wood, a block’s physical properties may be more vulnerable to certain environments, but overall wood is susceptible to damage when exposed to fluctuations in temperature and humidity. 

To glean more information about the wood that composes the printing blocks in the Huard Collection, we took samples from discreet areas that would not affect the aesthetic whole. Choosing the sample site is an important consideration. The samples must be a certain size (in our case no larger than a quarter of an inch) to see the structure of the grain vertically, horizontally, and radially. This data can tell us the genus of wood used and with that data we can figure out the specific physical properties. As of March 2024, we are still in the process of testing the wood, but we look forward to gathering more information when testing is complete.
French
Woodblock for Wallpaper, late 1700s
81 x 71.1 cm (31 7/8 x 28 inches)
Mary B. Jackson Fund 41.096

13 → RISD Museum conservator Ingrid Neuman in conversation with the author, September 2023.

To create finer details, some of the wooden blocks have metal elements. Composite pieces made up of different materials are especially prone to damage. Metal and wood have different physical attributes, and when exposed to the same environments and deterioration threats, these materials will have different responses. These differences often create more damage as the materials deteriorate due to their own unique instabilities, also known as inherent vice. 

The metal in these blocks can become damaged by fluctuations in humidity. The oxidation of the metal can create corrosion—evidence to the naked eye that its structure is deteriorating. Depending on the type of metal, different colors of corrosion can occur. Iron produces reddish orange rust, while copper often produces a green patina but can also produce red.13 Alloys, or mixtures of various metals, can have unique vulnerabilities.
Jacquemart et Bénard, manufacturer
Paris, France; 1791–1840
Wallpaper with Muses and Arabesques (before restoration), 1799
Woodblock print on paper 
115.2 x 119.4 cm (45 3/8 x 47 in.) Mary B. Jackson Fund 34.935
Jacquemart et Bénard, manufacturer
Paris, France; 1791–1840
Wallpaper with Muses and Arabesques (after restoration), 1799
Woodblock print on paper 
115.2 x 119.4 cm (45 3/8 x 47 in.) Mary B. Jackson Fund 34.935

14 → “The Deterioration and Preservation of Paper: Some Essential Facts,” Deteriorate Brochure, Library of Congress, https://www.loc.gov/preservation/care/ deterioratebrochure.html.

Decorators and homeowners often bought a surplus of wallpaper so that in the event of a tear or other damage, they could make the repairs that were needed. Because of this hands-on treatment, any repairs that appear to be original are an important part of the life of a wallpaper. 

The Huard Collection presents a broad range of condition stability and aesthetic challenges. There is no one-size-fits-all treatment, even for similar materials in the collection. Each wallpaper has its own unique history and life that it has lived. This particular wallpaper piece,  Muses with Arabesques (34.935), is undergoing treatment at Studio TKM Associates, a conservation firm located in Somerville, Massachusetts. Prior to their work, we were able to do some treatment at the museum. Many of the panels and fragments in the Huard Collection had, at some point in their history, been mounted to an acidic craft paper, pasted onto a canvas, and stretched onto wooden supports so that they could be displayed and stored vertically. We removed each panel from its frame, and many from their canvas backing. The brittle and acidic paper the wallpaper was glued to likely caused structural damage to the pieces. Acidity inherent within the cells makes the paper vulnerable.14 Using dry polyurethane sponges, we cleaned many decades of soot and dust accumulation from the face and reverse of each piece. The grime we picked up with the sponges was black soot, likely from the coal-burning furnaces and fireplaces commonly used earlier in the lives of these objects. We then placed the wallpapers in acid-free folders with acid-free glassine paper separating each piece to protect the surfaces. The folders are now housed in flat-file drawers.

15 → Chromium was patented in 1859. Pigments of course exist before they are patented and isolated, but they are often not widely available to artists until then.

The pigments used to color wallpapers vary widely. While the paper substrate of wallpaper is made up of organic materials, including wood pulp, the pigments in the paints may not be. Pigments made from inorganic materials are produced by grinding up rocks and minerals. They are not soluble in water and are able to maintain their solid form and physical properties throughout the painting and printing process. They are also not easily damaged when exposed to light. Using x-ray fluorescence, we can learn which elements are present in various colors. This technology helps us develop conservation strategies, and it can also allow us to trace production trends. Some elements were only utilized in particular time periods while others, like lapis made from the lapis lazuli mineral, at one time could only be mined from specific countries, in this case, Afghanistan. It can be possible to hypothesize a date for a wallpaper sample based on its pigments. For example, if there is a green color in a sample, and we find large amounts of chromium in our XRF data, we might know more about this sample’s date of production, as this pigment was not isolated until 1838.15 

We were able to test a number of wallpapers in the Huard Collection with generous help from the Brown University Geochemistry Department. In particular, Dr. David Murray, senior research associate and facility manager emeritus, and Jamie Pahigian, environmental chemical facility and lab coordinator, were very helpful with both their instruments, analysis, and expertise. Using a handheld Olympus XRF unit, we tested a grouping of different wallpaper fragments, borders, and sheets to find the presence of inorganic elements, specifically heavy metals, including arsenic. To learn more about these findings and the history of arsenic, please read Emily Banas’s essay.
Turner fig22_testing.jpg
From microscopic elements invisible to the naked eye to larger physical panels of wallpaper and all the materials in between, it is our responsibility to take care of all aspects of the Huard Collection. With the degradation process slowly marching on, we continually work to keep these objects safe for future generations. Continuing to learn more about the materials used in these works is vital to improving and evolving the ways we care for the collection.

Bibliography 
 

Arrowsmith, James. The Paper Hanger’s Companion: A Treatise on Paper-Hanging; in which the Practical Operations of the Trade are Systematically laid Down with Copious Directions Preparatory to Papering; Preventions against the effect of Damp on Walls; the Various Cements and Pastes adapted to the several Purposes of the Trade; Observations and Directions for the Panelling and Ornamenting of Rooms. Philadelphia: Henry, Carey, Baird, 1852. https://archive.org/details/paperhangerscom01arrogoog/mode/2up. 
  
Banas, Emily. “Deceptive Decor: Uncovering Arsenic in Eighteenth- and Nineteenth-Century Wallpapers,” Manual: A Journal about Art and Its Making 15, “Green” (2020). https://publications.risdmuseum.org/issue-15-green/object-lesson-deceptive-decor-uncovering-arsenic-18th-19th-century-wallpapers-emily. 

Bradshaw, William Richard. Wallpaper: Its History, Manufacture, and Decorative Importance. New York: Joseph P McHugh & Co., 1891. https://digital.hagley.org/PC_NK3400_B7_1891?solr_nav%5Bid%5D=4e92f533132c35b2c82f&solr_nav%5Bpage%5D=0&solr_nav%5Boffset%5D=9. 

Cennini, Cennino d’Andrea. The Craftsman’s Handbook. Translated by Daniel V. Thompson, Jr. New York: Dover Publications, 1960. 

Caswell-Olson, Bexx, 2023, Preventing and Responding to Mold in Book and Paper Collections, [Webinar]. [Online]. Northeast Document and Conservation Center, August 8, 2023. 

“Conserv-O-Gram.” National Park Service, 2001. https://www.nps.gov/museum/publications/conserveogram/19-24.pdf. 

Doerner, Max. The Materials of the Artist and Their Use in Painting. New York: Harcourt Brace Jovanovich, 1962. 

Frangiamore, Catherine Lynn. “Wallpapers in Historic Preservation.” National Park Service, 1977. http://npshistory.com/publications/preservation/wallpapers.pdf . 

FitzGerald, Christin, conversation with the author, November 2023. 

Fuga, Antonella. Artists’ Techniques and Materials. Los Angeles: Getty Publications, 2006. 

Gettens, Rutherford and George Stout. Painting Materials: A Short Encyclopedia. New York: Dover Publications, 1966. 

Hawksley, Lucinda. Bitten by Witch Fever: Wallpaper & Arsenic in the Nineteenth-Century Home. London: Thames and Hudson, 2016. 

Jones, Owen. The Grammar of Ornament. London: Day and Son, 1856. https://archive.org/details/grammarornament00Jone/mode/2up?view=theater. 

Kelly, Robert. “Historic Paperhanging Techniques: A Bibliographic Essay.” Presented in Lancaster, PA, 2011. https://wallpaperscholar.com/docs/HistoricPaperhangingTechniques.pdf. 

Laroque, Claude. “History and Analysis of Transparent Papers.” The Paper Conservator 28, no. 1 (2004): 17–32. DOI: 10.1080/03094227.2004.9638639. 

Library of Congress. “The Deterioration and Preservation of Paper: Some Essential Facts.” Deteriorate Brochure. Library of Congress. https://www.loc.gov/preservation/care/deterioratebrochure.html. 

Mayer, Ralph. The Artist’s Handbook of Materials and Techniques. New York: Viking, 1981. 

McClelland, Nancy. Historic Wall-Papers. Philadelphia and London: J.B. Lippincott Company, 1924. https://archive.org/details/historicwallpape00mccl/page/172/mode/2up?view=theater . 

Neuman, Ingrid, conversation with the author, September 2023. 

Pearce, Walter. Painting and Decorating. London: Charles Griffin & Co, 1898. https://ia800607.us.archive.org/34/items/paintingdecorat00pear/paintingdecorat00pear.pdf.