Anne Battram presented a shortened version of a talk given at the “first International Conference in Europe focused on upholstery history,” held in Vadstena, Sweden. Proceedings of the Sweden conference, “The Forgotten History- Upholstery Conservation” ed. Karin Lohm are available from Linköping University. Several people noted that this publication can be difficult to obtain- check with Anne or the University. Archetype may also have copies.
The talk gave an introduction to the history of slipcovers in America, and was jam-packed with specific examples and great visuals.
Anne explained that slipcovers have been used for seating furniture, footstools, and tables. They are often used to protect the surface below, which might be an expensive or fragile upholstery fabric, underupholstery, or finished wood. In a home, sturdy slipcovers might be removed to create a fancier appearance in honor of an esteemed guest. But in some instances, the slipcover itself is made of an expensive, extravagant material, and can be removed and stored when not in use. One example of a close-fitting, fancy slipcover was secured to the chair using cords attached to the cover, threaded through holes drilled in the frame.
Adding slipcovers to worn or outdated furniture has been used as a less expensive alternative to having them reupholstered. Slipcovers also allowed rooms to be re-decorated “en suite” with matching fabric for the upholstery, cushions, and window treatments.
Slipcovers are differentiated from dustcovers, which are used to protect furniture when it is not in use (e.g. in storage or when a house was closed). Dustcovers tend to be less form-fitting, usually extend all the way to the floor, and often are made from solid colored fabric.
Striped and checked fabrics were popular for slipcovers used to protect upholstery from everyday use. Sturdy chintz and toile patterns were also common. Colonial Williamsburg has an example of a leather slipcover.
Construction details vary: some examples of early slipcovers were made with the seams facing out and bound, (giving an appearance similar to welting) which would make the fitting process simpler and add definition to the final shape. Some slipcovers are very loose, barely fitted and might be attached with ties. Skirts and flounces added to a slipcover would give added protection to projecting curved or carved legs.
Check out the postprints, and the proceedings from the Sweden conference, for all the well-researched details on slipcovers.
Category: AIC’s Annual Meeting
Provides the membership with updated news about the annual meeting. Also announces themes, deadlines for papers, need for volunteers, etc.
41st Annual Meeting – ECPN Happy Hour sponsored by Tru Vue, May 29
This year, the Emerging Conservation Professionals Network’s (ECPN) Happy Hour was sponsored by Tru Vue, who generously provided food and drink tickets. It was a great success, with at least 100 attendees. Since the Happy Hour was on Wednesday, it was a great opportunity to mingle and relax before launching into the busy conference. It also directly followed ECPN’s Portfolio Seminar, which provided a nice segue and allowed participants to continue their conversation over food and drinks. We hope you’ll join us at next year’s Happy Hour in San Francisco!
41st Annual Meeting – Architecture Session, May 30, "An Evaluation of the Conservation History of Chagall's Les Quatre Saisons," by Jamie Clapper Morris
Jamie Clapper Morris, an associate at Wiss, Janney, Elsther Associates, Inc. presented this paper on behalf of Deborah Slaton, principal at Wiss, Janney, Elsther Associates, Inc. and herself.
Les Quatre Saisons is a mosaic by artist Marc Chagall, which is exhibited in a public plaza in the Loop district in downtown Chicago. It was a gift from Chagall to the people of Chicago in 1974, and it is located at the Chase Tower Plaza (formerly First National Bank of Chicago Plaza). The mosaic has tesserae placed on precast concrete panels with more than 250 colors. It was constructed in the Byzantine Style and assembled in southern France.
The original maintenance on this piece included biannual cleaning and annual sealing with silicon sealant. In 1988, the roof of the mosaic had completely deteriorated with 25% loss on the west side. In order to repair it, granite panels were put on the roof. In places where tesserae had fallen off, they were reinstalled in slightly different way in order to distinguish it from the original. In 1993, a bird deterrent gel was added but then removed because of staining. Visual assessment and lab studies were performed, including chemical analysis and scanning electron microscopy studies. The majority of the distress was on the west side. From 1995 to 1996, repairs were being performed on the adjacent plaza, and the mosaic was protected with an enclosure. A protective canopy was built for the mosaic, and wind tunnel studies were performed to ensure maximum protection. When repairing the mosaic, a lot of tesserae from the roof were used. The canopy was finished in 1996.
From 2009 to 2010, facade cleaning and limited condition assessments were performed, including some sounding and field microscopy. Expected distress was found. In 2011, a more detailed assessment was performed and it was sounded at 100% with xylophone mallets. Some expected distress included efflorescence and mortar loss. Limited maintenance was performed, including removing general atmospheric soiling, graffiti, and bird deterrent (which didn’t work). It was surface cleaned, and the graffiti was removed with acetone and water. Areas of loss were repaired and tesserae were re-installed. Ongoing maintenance is recommended.
41st Annual Meeting – Contemporary Art Session, May 31, “Automating Classification of Historic Photographic Paper from Surface Texture Images,” by Paul Messier
For over ten years, Photograph Conservator Paul Messier has been researching the physical properties of historic photographic papers—fibers, thickness, optical brighteners, and manufacturer markings. Most recently, Messier and co-authors* have been working to objectively characterize the surface texture of papers as a means to classify individual photographs as well as collections.
Using his personal collection of over 5,000 historic paper samples along with photographs from the Thomas Walther collection at the Museum of Modern Art, New York, photomicrographs of each surface were captured using a “texture-scope” available only at the Library of Congress and the National Gallery of Art. The images were then processed to abstract the features of the paper and allow for easier measurement of the distance between each vector height (i.e. texture peak). The data were sent out to various engineering teams with the goal of creating affinity diagrams that reveal patterns of paper matches. Although each team came up with a different methodology for matching samples, they all achieved results very similar to human detection showing a spectrum of matches from the same sheet of paper, same package, or same manufacturer.
With these successful results, Messier hopes to continue collecting images to be stored on an open-access database. Eventually, institutions and collectors should be able to upload their own photomicrographs and search within the system to discover affinities across a collection. This information about the paper’s manufacture can then be applied to connoisseurship and conservation purposes.
*This project was a collaboration between Paul Messier, Richard Johnson, James Coddington, Patrice Abry, Philip Klausmeyer, Andrew G. Klein, Eric Postma, William A. Sethares, Sally L. Wood, and Lee Ann Daffner. To read more, please see the studies listed on the Paul Messier website.
41st Annual Meeting – Photographic Materials Business Meeting and Luncheon, May 30, “Conservators as Diplomats,” by Mary-Jo Adams
The PMG luncheon was business as usual, with an approval of the minutes and budget, and a welcoming of the new committee, but we also had the privilege of hearing from Mary-Jo Adams, Executive Director of the Finca Vigía Foundation.
Founded in 2003, the Finca Vigía Foundation is an American organization developed to preserve Ernest Hemingway’s house and property in San Francisco de Paula, Cuba, about 12 miles outside of Havana. Hemingway lived in the house from 1939-1960 and it was opened to the public by the Cuban government after Hemingway’s death. In 2005, Finca Vigía (“Lookout Farm”) was deemed one of the National Trust for Historic Preservation’s 11 Most Endangered Places, and in 2006 it was added to the World Monument Fund’s 100 Most Endangered Sites. The house itself is still filled with original furniture, artwork, and other objects, including Hemingway’s car and personal library. During Adams’s talk, she detailed the work that has been done up to this point to restore the site to its original appearance.
The majority of funding for the Foundation’s preservation efforts comes from corporations, as donations to Cuba can be a bit tricky for the private sector. With that money, Adams and her team have been able to bring in specialists in architecture, engineering, and conservation to begin the process of repairing the estate and the collection. NEDCC has partnered with the foundation to consult on the conservation of archival materials, and photograph conservator Monique Fischer traveled to Cuba in 2012 to contribute to the efforts. All of the necessary materials were brought from the U.S. to treat, digitize, and re-house the books, papers, and photographs in the library collection.
Another part of the initiative includes the training of Cuban volunteers on site and in preservation classes and workshops held in Havana. As Adams described, the greatest challenge has been to collaborate with the Cuban people through their many cultural and language differences. For instance, the Spanish word for “endangered” roughly translates to “neglected,” so it is Adams’s job to explain the ongoing risks to the estate and best practices for its preservation. The title to the talk, “Conservators as Diplomats” refers to the need for cultural heritage professionals to work at gaining the trust of their foreign colleagues before trying to force help upon them…It also doesn’t hurt to have the assistance of international celebrities like Cuban-American home improvement guru Bob Villa, who not only advised on areas of the building repair, but has advocated for site’s preservation.
Adams expects that active restoration efforts of Finca Vigía should be complete by 2017. For more information, please visit the Foundation’s website.
41st Annual Meeting, Book and Paper Session, May 30, “Conservation of Dieter Roth’s Snow,” by Brenna Campbell, Scott Gerson, and Erika Mosier
[a conservation conundrum: “wait, later this will be nothing”]
Erika Mosier, Paper Conservator at The Museum of Modern Art, presenting on behalf of co-authors Brenna Campbell (Andrew W. Mellon Fellow in Conservation, MoMA) and Scott Gerson (Associate Paper Conservator, MoMA), highlighted some of the conservation and exhibition challenges presented by Snow, a major book project by Swiss-German artist Dieter Roth. Snow is the centerpiece of the MoMA’s current exhibition [February 17 – June 24, 2013] “Wait, Later This Will Be Nothing: Editions by Dieter Roth.”
Snow represents a transitional moment in Roth’s career, a movement away from his earlier Constructivist works towards more experimental book forms and explorations of entropy and decay. The treatment and exhibition of Snow not only posed an array of physical and material challenges but also raised questions about the biases, values, and long term considerations of our work as conservators. These considerations, as well as attempts to balance a respect for the integrity of the object with the artist’s intent, were further complicated by the fact that this particular artist was especially interested in material decay and viewed museums as “funeral parlors.”
Roth was commissioned make an artist book in 1964; over the course of three months, he produced thousands of drawings, prints, and notes in preparation, tacking them to the walls of his studio. Though the book was never published as originally conceived, Roth compiled a few hundred of the notes and drawings into a cardboard album and titled it Snow. In the late 1960s he fabricated a table and chairs to house and display Snow; the book was exhibited open on the table with a selection of pages removed and hung on the wall.
[Roth’s definition of a book: “a community of like-minded things”]
The mixed media nature of Snow posed a variety of conservation challenges. In addition to tracing papers, diazo types, printing proofs, plastic sleeves, and pressure sensitive tapes, the book includes a small wax still-life, paper cups, plastic tubing, and is housed in what is essentially a cardboard suitcase. Roth’s abundant use of pressure sensitive tape resulted in extensive damage, especially at the edges of the plastic sleeves where the deteriorating adhesive caused them to stick together. Sticky residue leaching from the PVC sleeves has made it difficult to remove items. A previous stabilization effort (initiated by Roth) involved adhering the tracing papers to cellulose acetate film, leading to structural and chemical damage.
Conservators also faced the challenge of attempting to determine the original order of the pages. Some elements appear to be missing and the conservators and curators had to guess at Roth’s original order, using clues such as evidence of stubs, lining up holes on the pages that were shot through with a BB gun, and comparing stains from failed adhesives. Roth was making changes to Snow into the late 1960s. For example, neither the plastic sleeves nor the cellulose acetate sheets were present in the 1964 version of Snow; these were added later at Roth’s request in order to stabilize the pages for exhibition. Though the artist added these elements, curators determined that they were not part of his original concept for the piece and since they had already caused irreversible damage, it would be acceptable to remove them in the course of conservation treatment.
Treatment goals for Snow included stabilization for handling and display, identification of materials used, and treating individual components for imaging. Removing the acetate linings allowed the tracing paper pages to move and drape more naturally. Torn tracing paper was then repaired with a 1:1 Lascaux:water heat set tissue. Acetone and xylene were used to reduce the staining and stickiness of remaining adhesive residues, and a water/ethanol mix was used to reduce stickiness on the PVC sleeves. Failing pressure-sensitive tapes were either removed or re-attached with PVA.
Snow is now displayed open on the table with many more elements displayed on the walls. Digital images of all pages can be viewed on a display screen in the gallery. In its current iteration, Snow does not function as a book but could technically be returned to book format if requested for use by a researcher.
41st Annual Meeting – Objects Session, May 31, "Beyond the Visible: Macro and Micro Analytical Forensic Imaging for the Documentation and Investigation of Archaeological Objects,” by Alexis North and Dr. Ioanna Kakoulli
There are two things you should know up front before you read this post. 1) This talk was fascinating. 2) I am not going to do it justice. I couldn’t take notes quickly enough and it didn’t help that I was frequently mesmerized by the beautifully colored images.
This paper briefly reviewed current methods for digital analytical imaging using visible, ultraviolet, and infrared light, but its true focus was on exploring and adapting technology from crime scene investigation for use in object examination. Specifically, the authors looked at the use of an alternative light source (ALS) combined with a different filters on a modified digital single-lens reflex camera (DSLR – modified by removing the UV/IR blocking filters). The ALS allows the user to choose specific wavelengths of light for illumination and, by using filters on the DSLR, reflectance/fluorescence can then be captured between 350nm and 1000nm. In this case, a Mini-CrimeScope 400 ALS was used along with a modified Nikon D90.
Multiple projects were featured to show the capabilities and limitations of the technique, all focusing on the investigation of archaeological ceramics. The authors began by creating reference panels of expected ancient pigments and binders, as well as of potential modern materials including adhesives. They then experimented to find successful combinations of excitation and emission. For one of the projects used as an example, an ancient Greek incense burner with a figure of Nike, this method of investigation was able to identify Egyptian blue and madder lake pigments. In this example, illumination was in the green spectrum and capture was in the red and vice-versa (if I’m remembering correctly). On a Roman figurine, the technique identified madder lake, but also pointed to the need for further testing of a green pigment which did not fluoresce (it turned out to be green earth). Additional examples included a Pre-Columbian ceramic and two Italian ceramics.
In summary, this paper demonstrated that forensic photography with a broadband light source can successfully be used for qualitative identification of a variety of ancient and modern materials. What’s exciting about this (at least for me) is its potential application to archaeological field settings. After all, crime scene investigation happens entirely “in the field” and this technique is completely portable. It also promises to be relatively simple once successful combinations are worked out for different materials. The ALS price tag is not exactly cheap, and the cost is likely to vary a bit depending on who’s buying (police department, university, etc.), but at roughly 15K it is in a more affordable category than, say, portable X-ray fluorescence. Plus, you end up with visually appealing and instructive images, which would frankly be great in both scholarly publications and museum didactics.
This paper also highlighted (for me) the debt we owe to graduate students like Alexis North (currently at the UCLA/Getty Program in the Conservation of Archaeological and Ethnographic Materials) and faculty like Ioanna Kakoulli (also at UCLA in the Materials Science and Engineering Department and Chair of the Conservation Program). Where would we be without graduate student research? Many of my archaeology colleagues will be delighted to know about this non-destructive possibility for investigating objects in the museum and in the field.
41st Annual Meeting – Objects Session, May 31, "Innovations During Renovations: Evolving Technologies and New Materials for an Encyclopedic University Museum,” by Carol Snow
If you were fortunate enough to hear this talk, you probably had the same thought I did: How can I get a job at the Yale University Art Gallery? In an action-packed twenty minutes, Carol Snow, Deputy Chief Conservator for the Yale University Art Gallery, took the listener on a fascinating tour of multiple conservation projects undertaken in conjunction with the Gallery’s 14 year-long renovation. The renovation itself involved three separate buildings, ranging in construction date from 1866 to 1928, and it dramatically expanded the Gallery’s exhibition, study, classroom, and conservation space.
The projects Carol chose to feature spanned an amazing range, and throughout her talk she emphasized the collaborative nature of each treatment and installation. Conservators, art handlers, exhibition preparators, and riggers – and in many cases engineers and architects – collaborated, as did artists. For an ancient Roman Mithraeum altar, for example, painted wall fragments were treated to remove old backing materials and then installed in their correct configuration in a newly constructed recreation of the altar. This was accomplished using an ingenious structure which allowed each fragment to “float” in place, supported. A scenic painter provided the final touches on the installation, integrating losses to give visitors a better sense of the altar’s original appearance and context.
Roman horse armor from Dura Europos (still backed with its original leather backing!) was installed on a fiberglass horse made from downloading a 3-D scan of a horse. A mosaic from a Byzantine church at Gerasa (Jerash, Jordan) was treated to remove the cracking concrete backing and newly mounted. Period rooms were investigated, pigments identified, and the wood panels dated by dendrochronology and then cleaned before installation. A fragile stained glass window by John LaFarge was supported and displayed on an interior wall using a clever system of hidden LED lights. For a slumping petroleum jelly dumbbell by artist Matthew Barney, conservators worked closely with the artist to recast a dumbbell from his original mold, using the correct composition of petroleum jelly.
Throughout the talk, the expertise and resourcefulness of the Art Gallery’s team was apparent. But it gets even better. At heart university museums are teaching collections, and although they serve to inspire the wider community, education and access are their primary missions on campus. Conservators are instrumental in achieving these goals, and Carol demonstrated this in spades. From her discussion of how a rooftop terrace was engineered to safely display outdoor sculpture, to her explanation of the Gallery’s clever use of steel-faced honeycomb panels and rare earth magnets to provide a simple and quick method for rotating displays of textiles, she highlighted the crucial role of conservators in achieving the Gallery’s mission. One of my favorite projects featured in this talk was a Marcel Duchamp Rotary Glass Plates sculpture. Conservators repaired a broken blade for this complex object, but then went on to assist in creating a working model of the sculpture which can be used for classes and workshops. Talk about engaging with artwork! Who wouldn’t appreciate seeing this in action?
In closing, I should say that I could not take notes quickly enough during this talk, and the projects I’ve mentioned here are not all-inclusive. So read the post-print! There’s something in this paper for every objects conservator, no matter your sub-specialty. There’s also something for any conservator interested in innovative solutions to tricky display questions or in ways of increasing context and access in the gallery. And if you’re looking for great models of teamwork in an institution, this is definitely for you. Congratulations to Carol and the YUAG team on a job well done.
41st Annual Meeting – Objects Session, May 30, "Rethinking the Monumental: A Creative Approach to the Preservation of a Landmark Tony Smith Outdoor Sculpture,” by John Steele and Abigail Mack
This talk had so much to like: an incredible case study of Tony Smith’s massive Gracehoper, a great film clip featuring 1970’s Detroit, and a nuanced look at how community and stakeholder values influence the preservation of public art. But most valuable was the clear exposition of the collaborative decision-making process that went into creating a treatment plan for this Detroit landmark.
Gracehoper is owned by the Detroit Institute of Arts and sits on the Museum’s north lawn. It’s the largest of Smith’s sculptures to be fabricated during his lifetime and is roughly 22 feet high and 46 feet long, with a whopping 3,800 square feet of surface area. Smith designed a cardboard maquette for the sculpture in 1961, but the full-size version wasn’t fabricated until 1972. In a delightful short film clip, we were able to see the fabricated steel sections being trucked into Detroit and listen to Smith talk about the joy of seeing this monumental sculpture installed. Although not part of the clip shown, Tony Smith mused that Gracehoper, “looks like someone’s nightmare…I guess the reason that it’s not my nightmare is because it’s on the lawn of the Detroit Museum.”
- Gracehoper at the DIA
41 years later the sculpture is, if not a nightmare, then a very challenging conservation project. The painted exterior – meant to be a “dull semi-gloss” black specified by Smith – is now faded, streaked and disfigured by graffiti. Corrosion has created rusty staining and caused paint to lift. The sculpture now desperately needs conservation treatment not only to restore its appearance, but also to insure its preservation for the future; unless existing corrosion is removed and the surface recoated, corrosion on outdoor sculptures like this one will continue, eventually undermining structural integrity.
The project team assembled to develop a treatment plan included conservators John Steele and Abigail Mack; John is the DIA’s Conservator of Sculpture and Decorative Arts, and Abigail, of Abigail Mack Art Conservation LLC, specializes in the conservation of modern outdoor sculpture. Also on the team were the DIA’s Associate Curator of Contemporary Art, Rebecca Hart; James Sejd, President of the industrial painting company ASCo; and Sarah Auld, Director of the Tony Smith Estate. Together, they considered the monumental size of the sculpture, its current condition, Smith’s desired aesthetic for Gracehoper, and current coatings technology.
Adding to the complexity of the project was the fact that as the team weighed treatment options, the DIA was facing an important regional tax vote which would, if successful, support operations for the Museum over the next ten years (it was successful, by the way). The Museum could not afford negative public opinion, and the Gracehoper project team knew that their recommendations would need to be sensitive to cost and feasibility as well as conservation goals. This was no mean feat for research and treatment on a sculpture of this size. It’s also worth noting that the DIA did an amazing job of raising funds for this project; the cost of treating Gracehoper will be paid exclusively by grants and private donations.
Ultimately, the project team decided to treat Gracehoper on-site and to repaint the surface using a roller-applied high performance paint. But the simplicity of this statement belies the complexity of the decision-making process. The team investigated every aspect of the sculpture’s current condition and evaluated an amazing number of treatment options. They were guided by 2 primary questions: 1) Could the sculpture be treated on-site or would it need to be disassembled and treated in an off-site facility? 2) What paint would best match Tony Smith’s aesthetics while also meeting the team’s requirements for durability, application, maintenance, and availability?
As a resident of metro-Detroit, I’ve watched the progress of this project with interest for several years. I was fortunate to have an insider’s look at the investigative process and clearly remember the massive whiteboard flow-chart in the DIA’s Objects Conservation Lab that tracked the group’s decisions as they worked through questions and weighed possible approaches. Although attendees of this talk didn’t get to see the whiteboard with all its scribbled queries and findings, John and Abigail’s talk suggested it by elegantly following the group’s comprehensive and carefully considered research. I suspect that this will be the most important and useful aspect of this paper for most conservators – not the details of the final treatment plan, since every painted outdoor sculpture is different and most are not as large as Gracehoper – but the way in which the team developed it.
For conservators considering similar projects with painted outdoor sculpture, or conservators considering ANY large-scale treatment project, this paper provides a great guide for what questions to ask and how to find the answers. Look for it in the OSG 2013 post-prints! Treatment of Gracehoper is slated to begin in July of 2013, so stay tuned to learn how it goes.
41st Annual Meeting – Book and Paper Session, June 1, “Testing the Waters: Applying New Techniques to the Cleaning of Acrylic Paint Film by Amy Hughes and Daria Keynan”
New York-based paper conservator Daria Keynan and Amy Hughes, third-year graduate student at NYU Institute of Fine Arts, shared exciting new contemporary cleaning techniques that have the potential for more effective and efficient treatment of paper-based objects by custom-matching the pH and conductivity modular stock solutions to the original object. This presentation was a wonderful and inspiring cross-specialty exploration of how paintings conservation techniques can be applied to paper conservation – and who doesn’t want more tricks up their sleeve?
Keynan was first introduced to the concept at the 2011 CAPS (Cleaning of Acrylic Painted Surfaces) workshop at the Museum of Modern Art. (I am now kicking myself for thinking that these workshops wouldn’t necessarily apply to my work as a book and paper conservator, so jealous!) To date there have been four innovative series of CAPS workshops supported by the Getty Conservation Institute to further the dialogue between theory and practice among conservation scientists and conservators as well as to introduce the concept of modular cleaning systems. Struck by her experience at the 2011 CAPS workshop and impressed by their use for treating acrylic paint films on art on paper, Keynan has further explored the use of pH and conductivity customization for other areas of paper conservation.
The CAPS workshop introduced several different cleaning techniques to minimize removal of surfactants when cleaning acrylic film surfaces. Acrylic paint and modern materials are scary (my word, not theirs.) Emulsions are often complex with many proprietary and artist-introduced ingredients. Colors react differently after drying, in treatment, and as they age. Some colors may be more sensitive to chemical and mechanical cleaning than others. Surfactants and other soft solids may never solidify, creating a tacky surface that can attract dust and grime. Conservation treatment, particularly aqueous treatment or mechanical cleaning with damp cotton swabs, can introduce immediate disfiguration like abrasion or swelling. Readily soluble surfactants can leach to the paint film surface or verso of the paper substrate. Treatment can also jumpstart deterioration that is not apparent until the future due to unknown chemical and mechanical consequences.
Of the many cleaning techniques available within contemporary conservation, Hughes and Keynan limited their presentation to the customization of pH and conductivity as a more finely-tuned and safer aqueous cleaning technique. They shared their methods by highlighting the treatment of works of art on paper brought to the Daria Keynan Paper Conservation in Manhattan for treatment where adjusted water – tweaking the pH and conductivity of the deionized water – was a key factor of success.
In the Garden (1986) by Paula Rego was surface cleaned to reduce dust and embedded grime altering the surface sheen. After dry cleaning with cosmetic sponges, Hughes tested various acrylic paint colors for pH and conductivity testing. Cylindrical pellets of cast agarose gel (recipe and supply information to be published in their BPG Annual post-print) were uniformly shaped with a medical-grade biopsy punch. (Heed Hughes’ warning, online image searches for “biopsy punch” are not for the weak-stomached!) The agarose pellet, acting like a poultice, was placed in contact with the acrylic paint film for 45 seconds to absorb the surface pH and conductivity. Agarose was selected because it imbibes the surface readings without visibly swelling the paint with excess moisture as in more aggressive techniques like local, direct application of deionized water. Keynan explained that the contact time of the agarose pellet can be matched to the estimated treatment time so that testing parameters can meet real-world treatment situations, increasing the predictability and reproducibility of testing results.
The pellet was transferred from the paper surface to the well of a pocket-sized, hand-held pH meter (Horiba Laqua pH Tester from Cole-Parmer) to record the pH of the paint surface. A droplet of deionized water was then placed on the pellet and transferred to another pocket-sized, hand-held conductivity meter (Horiba B-171 Twin Conductivity/Salinity Pocket Tester from Cole-Parmer) to record the conductivity of the paint surface. (As someone who absolutely dreads calibrating our cumbersome pH meter I was overjoyed to hear how easy these were to use – my purchase order request is already submitted.)
The conservators used the recorded pH and conductivity for a given area of the painted surface to identify the optimal working solution for cleaning. They selected from among a variety of premixed stock solutions that were created according to the CAPS workshop directions using deionized water, glacial acetic acid, and ammonium hydroxide in a range of ph 5-8 and conductivity 1000-6000 µS (micro Siemens.) Once mixed, the stock solutions can be stored in the refrigerator for up to several months. Keynan also reported that they often add several drops of an antimicrobial preservative for a longer shelf life.
The embedded material and dust on In the Garden released easily with 3-4 passes of lightly damp, pre-blotted cotton swab rolled over the surface. Hughes warned that since acrylic film is susceptible to abrasion it is important to monitor the paint surface during treatment. Cotton might not be appropriate for all acrylic surfaces so additional experiments with different swab materials may be useful. Similar success was seen in the mold removal and stain reduction of Maquette for Smoking Cigarette Relief (1983) by Tom Wesselmann.
Since Superstorm Sandy hit New York City in October 2012, Keynan’s studio has seen many complex treatments because of the unusual and unknown composition of the storm water which was often contaminated by sewage (uh, gross.) Many of the paper-based objects were stained with tidelines that were difficult to remove and fluoresced brightly under UV. Standard paper conservation techniques often visibly removed the tidelines but were deemed unsuccessful since under UV they shifted along the paper fibers or sank but were not completely removed from the paper support. She related that altering the pH and conductivity of her treatment water dramatically improved treatment results. Removal of the fluorescing blue tidelines (both external and internal) was achieved by local application of the adjusted water and using fumed silica poultices to block the formation of new tidelines.
The last example Keynan shared was a sample of naturally aged 2-ply paper board. (This was exciting, anyone else ever stare blankly at a nasty tideline on an illustration board and just sigh?) Traditional and adjusted treatment waters were applied with cotton swabs in several passes to clean the surface with varying results. Traditional deionized water cleaned less and was uneven, leaving a soft and vulnerable surface. The solution set at pH 6.6 and 6,000 µS glided more easily and had more even results. It also felt more controllable when working. The third sample solution set to pH 5.5 and 14,000 µS gave the most effective cleaning but in real life would probably not need three passes. After drying, the surface readings for all three areas had almost identical conductivity and pH readings.
Keynan concluded that by matching a pH- and conductivity-adjusted solution to the surface of the object it is possible to create a near chemical equilibrium at the surface to eliminate leaching from or depositing into the paint film. In treatment, using adjusted solution equals maximized cleaning efficiency with less wetting out of substrates, less pigment transfer, less repeated action, less loss of surface texture, and reduced distortion of the working area. Conservators have always adjusted pH for various uses, but by measuring the conductivity we can tailor our treatments to the physical needs of the object material with more refinement and subject it to less invasive treatment. Adjusted waters are an incredibly useful tool for improving and refining treatments in our conservation practice.
Hughes and Keynan’s presentation was an approachable and exciting take on the contemporary research going on in the field of conservation science and paintings conservation, especially as led by Chris Stavroudis (freelance paintings conservator in Los Angeles) and Richard Wolbers (Winterthur/University of Delaware Program in Art Conservation) in, well, all things related to cleaning painted surfaces and the Modular Cleaning Program.
Other presentations at the AIC meeting in Indianapolis such as “Mass Spectrometric Imaging of Acrylic Emulsion Paint Films: Engineering a Microemulsion-Based Cleaning Approach” (Paintings + Research and Technical Studies Thursday, May 30) show that the MCP and CAPS research continues. During the question-and-answer period Dr. Anthony Lagalante (Villanova University) shared that he and Stavroudis had recently recorded a video about using and calibrating the meters – it was on the cutting room floor, but will be posted to the CAPS website soon. Lagalante also sent me a link to their illuminating Studies in Conservation article that is currently available as a pre-print:
C.E. Dillon, A.F. Lagalante and R.C. Wolbers “ Aqueous cleaning of acrylic emulsion paint films. The effect of solution pH, conductivity and ionic strength on film swelling and surfactant removal” Studies in Conservation 57(1), (2014). http://www.ingentaconnect.com/content/maney/sic/pre-prints/2047058412Y.0000000076
The concept presented by Hughes and Keynan in “Testing the Waters” has the potential for wide application for all book and paper conservators. Working with stock solutions is a fast and economical lab practice. Customizing treatment solutions increases the workability and effectiveness of the treatment. Many of us in the room instantly coveted the easy-to-use digital meters as we thought of the hassle of calibrating traditional models. I’m intrigued by how this research can be applied to aqueous treatments meant to introduce alkaline reserves to acidic paper.
This was a welcome multi-disciplinary presentation that encouraged conservators from other specialty groups like PSG and RATS to attend the BPG program. I am not alone in hoping for more presentations like it at future meetings so we can all benefit from the exciting things happening in all areas of our conservation community.