Photograph conservator Diana Diaz introduced her presentation as a study case which deals with “overwhelming protection” of photographic materials.
The project started in 2006 when the Harry Ransom Center acquired the photographer Arnold Newman’s archives, including various photographic and other materials, such as photographic albums, sketch books, documentation of many projects… and color transparencies.
More precisely, a corpus of 35 mm Kodak Kodachrome color slides in plastic mounts was found. The slides were wrapped together with sealing tapes, forming in 16 sets. The tapes displayed, on the edge of each pack, handwritten inscriptions indicating the dates and subjects of the photographs. The dates inscribed on the tape enabled to date each project, the whole collection ranging from 1954 to 1972. Diana Diaz showed several examples of the images, like one taken for a project shot in Spain in 1970 for Holiday Magazine.
These slides series are of interest as they inform on the photographer’s working methods. For instance, they showed different cropping, compositions, and exposures experimented within each series. One can see how Newman would play with lights and colors and produce variations of the same images, among which he would then make his final selection for the publication. Diaz then listed all the assignments projects covered in the slides, shot in various places (Spain, Canada, California…) for different magazines, such as Harper’s Bazaar or Life.
However, when the slides were found, the images were still inaccessible since after the removal of the tape applied on one edge displaying the inscriptions, another white tape underneath maintained the stacks of slides together. Three types of tape were identified among the 16 sets:
a masking tape;
a discolored white tape;
a white tape still tacky.
The conservation treatment needed then was difficult to engage because the tapes were in contact, not only with the slides mounts, but also with the films themselves – on both the image and support sides.
Therefore, to remove the tape carrier, Diaz logically proceeded by types of tape.
The white tape still tacky was removed mechanically with a spatula, without any adhesive residue left at the end of the treatment.
The masking tape was strongly adhered and did require a heated spatula combined with the use of solvents.
The discolored white tape was removed with the help of water vapor.
After all the carriers were removed, Diaz evaluated the materials and condition of the residual adhesives in order to determine which solvent to use. She referred to Smith et. al.’s paper1, which not only presents the history of pressure sensitive tape and their ageing properties, but also appropriate solvents and suitable methods of application for their removal. Thus, Diaz used naphtha (a mix of hydrocarbons) to successfully remove the rubber-based adhesive, and ethanol for the oily adhesives. The solvents were applied gently with a cotton swab in a circulation motion and in one direction to minimize the scratches and increase the efficiency.
The photographic documentation under Ultra-Violet illumination allowed to assess the removal of all the adhesives. Finally, the slides were individually rehoused in conservation materials.
Although this treatment was successful, several questions are being raised: Are there remaining solvents residues in the photographic materials at the end of the treatment? Has the surface been scratched? Indeed, the topic of the effect of solvents on color transparencies, in particular regarding the innocuousness for the photographic materials, would require further research to help photograph conservator to choose a suitable treatment.
1 Bibliographic reference: Merrily A. Smith, Norvell M. M. Jones, Susan L. Page, & Marian Peck Dirda. “Pressure-Sensitive Tape and Techniques for its Removal From Paper”
JAIC 1984, Volume 23, Number 2, Article 3 (pp. 101 to 113 http://cool.conservation-us.org/coolaic/jaic/articles/jaic23-02-003.html
APOYOnline (Association for Heritage Preservation of the Americas) is a non-profit organization that facilitates communication and exchange among heritage preservation professionals throughout Latin America and the Caribbean region. Beginning August 30 and extending until September 2, 2016, APOYOnline hosted its first regional conference and workshop in Medellin, Colombia. Attended by 73 participants from 15 countries, the theme of the conference was “exchanges and practical tips”. While presentations focused on a range of cultural materials, the primary emphasis of the conference was on preservation of photographic heritage due the importance of photograph collections in Latin America and the immediacy of addressing these collections. Based on the presentation given at the Annual AIC Meeting, the APOYOnline conference appeared informative, fun, well-planned, well-received, and resulted in successfully engendering international collaborations.
Image courtesy of the APOYOnline Facebook page
Colombia was chosen as the conference host country because of its central location within Latin America, and Medellin as the host city to promote the revitalized city. Logistical planning for the conference required coordinating team meetings across four different time zones, taking full advantage of communication technology such as WhatsApp and Skype. In addition, there was an incredible amount of fundraising to support the conference and its participants. Major initial backing came from Tru Vue, Banco de la República, and the University of Delaware, which then attracted more supporters, resulting in a total of 21 financial donors. Through this campaign, APOYOnline was able to provide scholarship to all 73 participants – 60% partial grants and 40% full grants for conference attendance.
The program was divided into two major sections: paper presentations in the mornings and workshops in the afternoons. In total, the conference had 14 papers and 24 poster presentations. Paper topics focused on a wide range of preservation and risk management projects, including education, storage, collections care, impact of microbiological research, emergency response, treatment of ceramic murals, and more. In addition, posters discussed glass plate negative collection preservation, conservation of audio visual materials, and paper conservation in tropical climates among other topics. All sessions were recorded and made available on the APOYOnline webpage for free. The workshop on conservation of photographs involved lectures, discussions, and hands-on demonstrations about identification and preservation of photographic materials and were translated into three languages for all participants. Originally intended for 25 people, the conference organizers were eventually able to open the workshop to all attendees. Some of the most important issues for photograph collections in Latin America include immediate inventory, cleaning, storage, and preventive preservation. The workshop therefore provided participants with a better awareness of the needs for their collections and information that they could then bring back to their institutions.
Image courtesy of the APOYOnline Facebook page
During the conference, there was a meeting with the participants entitled “Vision 2020” in which the future of APOYOnline was discussed. Suggestions from the session included hosting more events, dissemination of activities, and research. APOYOnline is therefore working to strengthen networks with universities, provide more professional training, and act as an international bridge by bringing people to Latin America and vice versa. The organizing team for the conference received a large amount of thank you notes from attendees on how the meeting impacted their work and collections. The next APOYOnline conference will take place in Antigua, Guatemala to advocate more for countries in Central America and the Caribbean region.
Further information about APOYOnline can be found at www.apoyonline.org as well as through Twitter, Facebook, and YouTube.
This talk was a good example of collaborative art historical and material science research. Two of the three authors, Kaslyne O’Connor and Ariel Pate, discussed a study that revolved around two gum-platinum prints by Edward Steichen from his 1904 “Moonrise” series in the collection of the Art Institute of Chicago that had titles and dates under question. Each print had been referred to by different names (“Midnight Lake George” and “Moonlight Lake George“), and varied in tonality and surface sheen (you will notice that the prints have the same titles and dates on the Art Institute of Chicago website). Furthermore, the image in one of the prints is flipped horizontally.
A letter from Steichen to Stieglitz talks about “Midnight Lake George” being a platinum print followed by blue print, then greenish gum varnish. This letter is a valuable piece of information, along with X-Ray Fluorescence and Fourier Transform Infrared Spectroscopy that gave characteristic signals for Prussian blue, platinum (“Midnight…” had more), palladium, mercury (traces in “Midnight…” only), chromium, iron (“Moonlight…” had more), and lead for both prints. Still to be determined is the distribution of Prussian blue throughout the print, which would suggest the cyanotype process vs. a Prussian blue watercolor wash over the entire surface of the print. Clip marks at the print edges did displace the gum layer, thus revealing a blue layer below, which could be a hint that the cyanotype process was used. Examination of “Midnight…” under ultraviolet light exhibited a green fluorescents characteristic of linseed oil.
A Camera Works supplement from 1906 refers to “Moonlight…”. A 1910 Albright Art Gallery catalog for the “International Exhibition of Pictorial Photography” refers to “Moonlight…” having been made using a platinum gum process “peculiarly [Steichen’s] own”. Ultimately, a timeline was proposed by the authors using the information gathered from this research, which supports the 1904 (“Midnight…”) and 1909 (“Moonlight…”) printing dates for each. More apt titles were also proposed–”Road to the Valley, Moonrise” for “Midnight…” and “Road to the Valley, Moonrise Lake George” for “Moonlight”. Something that was noted that I found to be particularly interesting was that Steichen became less “poetic” in his later years, and retitled many of his prints.
Also to note, this project was born out of a previous project to create the website The Alfred Stieglitz Collection, a rich resource recommended to visit.
Nathália Vieira Serrano’s talk focussed on the “incorporation” and “disincorporation” (accessioning/deaccessioning) of archival documents in the Department of Archives and Documentation at Casa de Oswaldo Cruz, in Fundação Oswaldo Cruz, in Rio de Janeiro. She discussed the overarching framework that was developed to help guide decisions of accessioning and deaccessioning collection materials, and then as a case study, the application of this framework to a specific collection–a collection of history of science of public health. This collection consists of glass plate negatives, roll and sheet film, all by various photographers and on different themes including, history, health education, scientific divulgation, and life sciences. A survey determined that the images were still in good shape, as were their supports.
The talk was a nice example of the challenges staff in the world of preservation face when needing to determine what can stay and what needs to go, the many factors to consider, and the criteria and prioritization to establish when making such important decisions. Serrano mentioned the mission of Casa de Oswaldo Cruz, the difference between multidisciplinary vs transdisciplinary, and the different stakeholders (researchers, collection managers, and potential current and future interested parties) that are taken into account. She also referred to Salvador Muñoz Viñas writings on contemporary theory of conservation and his statement that conservation is not a neutral act.
I appreciate how it is difficult to convey fully in a 20-25 minute talk the complexity of these types of projects. There are so many interesting points to think about, large and small, and people from different points of interest that are part of the decision making process. If there is one area I would have been interested in learning more about, it was some similarities and differences in their approach when compared to other national and international institutions. The presentation also gave insight to a large collection in Rio de Janeiro, how it is stored, and the building and environment that surrounds it.
Two questions that were asked after the talk were:
Is cost considered when deciding whether or not to deaccession? Answer: The survey is still underway, but cost will likely be considered.
What is the size of the collection? Answer: Still to be determined. (But an image was shown of the storage area the collection takes up)
As a library conservator, I enjoy breaking out of my niche by attending art-related talks, because it gets me back in touch with my roots as an artist once upon a time. I knew Samantha’s talk was not to be missed. She has shown through previous research that the conservation of modern and contemporary art on paper is exciting, as you often have a more direct link to the artists when treating their work. While the Hungarian-born artist Sari Dienes (1898-1992) is no longer living, I was confident Samantha would still get to know the intricacies of this unique artist thoroughly. There has never been a better, more urgent time to focus on the influence and mastery of women artists as it is now, in our current political climate, where suppression of the female voice rises as a concern once again. Samantha’s timely and engaging talk grabbed my attention not only for its focus on an unsung 20th century female artist but for the way Samantha, paper conservator at the Virginia Museum of Fine Arts (VMFA), throws herself into her projects wholeheartedly.
By now many colleagues have heard about Samantha’s research and treatment of original artwork by the tattoo artist “Sailor Jerry” during her time as paper conservator at CCAHA. I admired how much her work on this project became a part of her, literally and professionally. The tattoos she took away as a permanent “souvenir” of this work, on her own skin, really left an impact on me. Having overlapped with her in grad school at Buffalo, I remember how much Samantha loves her work and shows a special curiosity. Samantha’s project on Sari Dienes’ large-scale rubbings was no exception.
While Dienes worked in many mediums and styles throughout her lifetime, Samantha presented Dienes’ rubbings of manhole covers, which she created using brayer-applied ink on Webril – a material used in the medical field as padding between skin and cast. While Webril today is commonly 100% cotton, it was not in the past, and the fiber composition of the Webril Dienes used was not recorded. True to her immersive spirit, Samantha travelled to the Sari Dienes Foundation in Pomona, NY, where she was able to collect historic samples of materials from the artist’s collection to use for testing and analysis. She explained that identification is not resolved as she seeks colleagues with fiber samples she might use for comparison, since her reference library did not provide a match to her FTIR analysis.
Samantha Sheesley creates a rubbing of a manhole cover in the style of Dienes
In her presentation, Samantha led the audience on a manhole scavenger hunt through the streets of NYC, where she traced Dienes’ steps at the artist’s preferred working time, Sundays at 5am. Samantha wondered how Dienes navigated the city streets with all her required bulky supplies, and explained that Jasper Johns sometimes served as her assistant. Dienes would talk to people passing by on the street as she worked, which is inevitable in the extroverted city of New York. To get a sense of the physical work required, Samantha produced rubbings in the same manner as the artist.
It’s impressive how well-connected Dienes was to artists of the time, but because she was a woman, she was not well-liked or accepted by the many of her male contemporaries. Jackson Pollock spoke poorly of her, but she collaborated with Jasper Johns and Robert Rauschenberg for an exhibit in the Bonwit Teller department store in 1955. The VMFA acquired two of the manhole rubbings that were at Bonwit Teller, which were in poor condition. One of the pieces Samantha focused on is titled “Marcy.” It was stapled to an acidic cardboard backing, which subsequently discolored the Webril, along with displaying many other condition problems.
Samantha Sheesley treats “Marcy” at the VMFA
The goal was to repair Dienes’ work in order to restore her legacy and display all the manhole rubbings together again. After much testing on samples, Samantha decided to wash the delicate Webril supports using wet Tech Wipe, and created over 70 inserts using acrylic-toned Hanji adhered with methyl cellulose. Pastel pencils were used for visual integration. The work was logistically challenging and time consuming, to say the least, but the audience was able to see clearly how much care was taken with excellent results depicted in Samantha’s treatment photos.
I was thrilled to be exposed to an artist I never heard of, but who was in fact so very influential. Samantha explained that Dienes’ work not only influenced Rauschenberg and Johns, but was associated with Fluxus artists such as a personal favorite, Naim June Paik. Dienes believed any material could be used to create a work of art and to end her presentation, Samantha shared an inspiring Dienes quote that deserves to be passed along: “Spirit lives in everything. It has no age, no color, no sex.” Samantha should feel proud of sharing the life and work of a woman who influenced many, while standing in the shadows of history. One of our greatest responsibilities and joys as conservators is to repair artifacts so that silenced voices can be heard once again. Samantha continues this charge with admirable determination.
This year ECPN rolled out a new program during a pre-meeting session that allowed poster presenters another venue to share their projects and research. I was very excited for this session because I have felt overwhelmed by the number of posters and limited free time to view them. A similar sentiment was later echoed at the AIC Business Meeting. I hope that ECPN (or AIC generally) considers organizing a similar session next meeting and I would encourage anyone looking for more engagement with poster authors to attend.
This session was in no way comprehensive of all the poster submissions. ECPN members received a notification about the session about a year before the meeting. However, ECPN contacted all poster authors once they were accepted to the general AIC poster session. The email solicitation encouraged “emerging conservation professionals” and “topics relevant to ECPs (not necessarily authored by ECPs)” according to Rebecca Gridley, ECPN Vice Chair and one of the organizers of the session. There were 14 presenters total this year, which were chosen from email responses of poster authors indicating an interest in participating. The final selection was chosen to offer a range of talks across specialties and include speakers spanning the ECPN demographic, according to Gridley. Unfortunately not every author interested was able to be included due to time restraints of the session, but ECPN is considering how this could be improved in the future.
This year’s inaugural Lightning Round did seem to have mostly young presenters including pre-program, graduate students, and recent graduates. It does seem that ECPN is trying to be more inclusive and the demographic of “ECP” is only loosely defined. Certainly the audience this year was more diverse than the presenters and included AIC Fellows and other more established professionals in the field. At the same time, the environment of the Lightning Round felt very safe and welcoming. We were seated at round tables, which was more casual than auditorium seating. This was a great opportunity for first-time presenters to get their feet wet. One of the speakers was a first-time attendee and presented on her first conservation treatment ever as a pre-program. This session promoted information sharing and dialogue—activities that I personally feel will only help strengthen our field.
Alex Nichols reflecting on the benefit of the Lightning Round said, “I was approached by several conservators and researchers in specialties other than my own [modern and contemporary objects] who said that they were introduced to my research through the lightning round presentations.” In comparison to the last time Nichols presented a poster (at the 43rd Annual Meeting in Miami), she had more people ask about her research, which she attributes to the exposure from the ECPN Lightning Round.
Cathie Magee presenting alongside Michiko Adachi at ECPN Poster Lighting Round. The moderators are seated at the table.
The 14 poster topics were divided into two rounds, which allowed for a necessary intermission/bathroom break. The rounds were moderated by Michelle Sullivan, ECPN Chair, and Rebecca Gridley, ECPN Vice Chair.
In the spirit of the “Lightning Round” each presenter was given two minutes and three content slides to summarize their poster at the podium. This seemed like a daunting task and like I might not receive much more information than the title of the poster. I was really impressed with how clear and concise all the speakers were (I think the tambourine—symbolizing time’s up—only had to be used once). I learned a lot from the brief presentations and there was even time for one or two questions for every speaker. Having the visual component of the slides I felt took this beyond what a written abstract can offer. The Q & A was also very lively and I think emphasized how valued the poster presentations are to the conservation community.
I found this Lightning Round useful not only for the direct information, but also in helping me be more efficient with my time in the exhibition hall with the posters. Each PowerPoint included the poster number for easy reference to the location in the exhibit hall. Feeling similarly, Claire Curran, Assistant Objects Conservator at the ICA, also in attendance, and reacted, “definitely visiting this one—sounds really cool” in response to a treatment of a Hopi Katsina doll. The room was filled and there seemed to be a strong positive response to the session.
To keep things light and encourage additional networking during the ECPN Happy Hour (which immediately followed the Lightning Round) a fun fact about each presenter was announced in addition to his/her professional bio. For example, Sarah Giffin was introduced as the “meat whisperer” because of her delicious slow cooking brisket recipe.
I am embarrassed to say that I did not know that the posters are published on the AIC website after each Annual Meeting. You can access them here.
To help your exploration of the .pdf files online, here are some of the highlights each presenter chose to emphasize during the ECPN Lightning Round.
#30 Conservation in Miniature: The merger of museum object and historic interior in the treatment of a Victorian era dollhouse
Sarah Giffin
Applied in situ treatment methodology used for full-scale interiors to miniature interior of Horniman dollhouse
Mist consolidation with nebulizer using Klucel G in acetone (tests in water solubilized tannins in wooden walls creating issues with tidelines)
Condensation in the small tube was a challenge and had to tap out liquid droplets at times
#60 Conservation and Art Historical Data goes Digital at the Art Institute of Chicago
Kaslyne O’Connor
Interactive website for conservation treatment of a collection of Alfred Stieglitz photographs and some contemporaries
artic.edu/Stieglitz
Used WordPress platform because easy interface and allowed for frequent updates to content
Provides links to art historical information as well conservation/ technical information and research
#44 Applying Fills to Losses in a Flexible Polyurethane Foam Chair at the Museum of Modern Art
Alex Nichols
Research and analysis to confirm type of foam composition of the chair
Bulked methylcellulose and grated polyurethane foam for consolidation and filling of losses; liquid nitrogen helped harden foam enough to easily grate and shape
Inpranil DLV/1 is a traditionally favored consolidant for polyurethane foam but has been challenging to acquire
#92 Chemical Cleaning and Intervention Criteria in a Brass Dial Clock from the XIX Century
João Henrique Ribeiro Barbosa
Clock face (only surviving element of the clock) composed of three different metals joined together with rivets
Previous cleaning by polishing left white residues and new corrosion products developed underneath
Ammonium citrate solution addressed polish residues with “DTCNa” or sodium diethyldithiocarbamate solution addressed corrosion products
#24 History, Treatment, and Preparation for Digitization of 14th-century Estate Rolls
Annabel Pinkney
Surface cleaning, humidification, repair with Japanese tissue
Rehousing to handle during treatment, digitization, and future research
#42 Treatment and Reconstruction of a Badly Damaged Hopi Katsina Doll Made of Gourd
Hayley Monroe
Gourds painted in acrylic
Treatment included surface cleaning, consolidating cracks, introducing new internal armature to help with reassembly and stabilization
Used silicone self-adhering bands to secure while mends were setting
Armature was set in place before doll head was reattached; tensioned wire extending to wings before head was placed back on
#10 Towards Nondestructive Characterization of Black Drawing Media
Nathan Daly
Redon drawings were used for case study
Redon working period overlapped with commercial materials available in 20th century
Macro XRF scanning used to map elements combined with micro Raman spectroscopy
Characterization relied on peaks in fingerprint region and peaks indicative of known additives to distinguish between different carbon-based media
785nm laser for Raman because of heavy use of fixatives on the drawings
#27 (I Can’t Get No) Documenation: Preservation reporting in the Archives
Marissa Vassari
Established a template “Preservation Report” for standardized documentation and condition reporting
Focus on up-to-date condition and documentation of current status of projects and personnel involved; address realities of institution with changing/temporary staff and disruptions project workflow
Format based on feedback from other institutions and existing condition reports in the archive
#80 Bedbugs: A pesky problem
Meredith Wilcox-Levine
Addressing infestation of a Lakota teepee in private hands installed behind owner’s bed
Freezing unsuccessful likely not able to achieve low enough temperatures throughout
“Solarization” using hatchback car appeared to work (i.e. no live bugs remained)
For domestic infestation chemical treatment often necessary for bed bugs; they are night feeders and hide during the day
#32 Treatment of a Shattered Bark Basket from Australia
Marci Jefcoat Burton
Basket likely eucalyptus bark sealed with natural resin
Consolidated with B-72; bridged with tissue and blend of Lascaux adhesives
Removable internal support for storage constructed of backer rod (trapezoidal shaped Ethafoam strips) shaped to the contour of the basket and padded with Volara
#84 Lifting the Microfiber Veil: Utilizing Evolon fabric at the Mauritshuis to remove aged varnish from Hendrick Heerschop’s A Visit to the Doctor
Julie Ribits
Evolon is 70:30 polyester: polyamide spun-bond fabric
Evolon originally developed as anti-bug fabric
Used to lift and remove aged varnish; gentle and appropriate for surfaces with extensive lead soap networks
Polyamide fibers are hydrophilic and contribute to aqueous cleaning
#22 Captain America Encounters Klucel M
Michiko Adachi and Cathie Magee
Captain America pages had been stapled together in case binding
Mending utilized solvent reactivated tissue to avoid solubility issues and tidelines from acidic migration of newsprint substrate
Klucel M used as adhesive because of strength and transparency
Klucel M artificially aged by Library of Congress and seems to have similar properties/behavior to Klucel G
#67 Initial Treatment Techniques for Japanese Lacquer-based Metallic Thread and Cut Paper Applique
Elinor Dei Tos Pironti
Solubility testing was used to characterize original adhesive for metallic paper threads on a Japanese garment
Urushi was used to consolidate metallic threads
#31 Under Close Observation: A pilot study monitoring change in objects’ conditions
Ashley Freeman
Summarizing current research and findings of the Managing Collections Environment Initiative at the Getty
Comparing different methods of monitoring conditions of objects including photographic documentation (DSLR, point and shoot camera, iPhone), caliper measurements to monitor cracks, acoustic emissions
14 objects representative of materials found in institutional collections used for case study; exposed to humidity cycling
Remy Dreyfuss-Deseigne described research related to mending methods for transparent materials using nanocellulose films. His research has been carried out with several institutional partners, at the National Library of France (BnF, Paris, France), Research Center for Conservation (CRC, Paris, France), French Museum of Cinema, and during his 2015-2016 NEA fellowship in paper conservation at the Conservation Center for Art & Historic Artifacts (CCAHA, Philadelphia, PA).
Remy opened with some images of difficult structural problems: torn gelatin windows, animation cells, and architectural drawings on tracing paper. He then introduced nanocellulose, explaining how it is made, what its properties are, and its potential for use in conservation.
His work focuses on one kind of nanocellulose, microfibrillated cellulose (abbreviated MFC). Nanocellulose materials are produced for a variety of uses in electronics and biotech, and are being researched and manufactured by several universities including in Grenoble, France and at the University of Maine.
Nanocellulose is produced by mechanically shearing wood to rip apart the fibers until they are nano in scale. Cotton, spruce and birch can all be used as sources for nanocellulose. The amorphous parts of the remaining cellulose structure are treated with acid in order to dissolve them, leaving highly crystalline fibrils. There is a lot of ongoing research into the production of nanocellulose in the nanotechnology, renewable materials, and sustainable engineering fields.
Nanocellulose fibrils vs. crystals, image from: https://3dprint.com/69012/american-process-and-ornl-say-nanocellulose-will-rival-carbon-fiber-for-3d-printing/
For conservation applications, Remy compared the properties of nanocellulose films to lightweight Japanese papers like gampi and kozo used to mend tears on translucent artworks. Nanocellulose is supplied as a gel that can be cast out by pouring into a petri dish and evaporating out the water, creating films that vary proportionally in thickness related to concentration. Remy’s research investigates its properties in combination with different adhesives, and its response to artificial aging tests (light, temperature and humidity) as well as mechanical strength tests.
He found that the nanocellulose films were thinner than papers but quite strong (nearly as strong as Gampi), and mostly behaved like cellulose, a good thing for their use as a paper conservation material. Most importantly, mends made with the thin films are practically invisible in regular and transmitted light. These mends were demonstrated on translucent slides with tears from the collection of the French Museum of Cinema (impressive work!). Ongoing testing will include further analysis of the material, e.g. pH and mechanical strength measurements and fungal resistance tests.
While this was the first time I had heard about nanocellulose it has many potential uses, and not just for mending translucent materials. As a biomaterial derived from renewable forestry resources, nanocellulose has gotten a lot of attention over the past five years for its potential in industrial applications. Given its high ratio of strength to weight it has great potential for use in fill materials of all types, and has already found applications in industrial 3D printing as a substitute for carbon fibers in composites. Since it is compatible with many adhesives, it may find wide-ranging applications in conservation. I am looking forward to hearing more about Remy’s ongoing research and thank him for the excellent introduction to an interesting material. You can learn more about Remy’s work at his website.
Jan Cutajar is Research Assistant at the University College of London, and Hana Bristow is Assistant Conservator at the National Museum of the Royal Navy, Portsmouth. They jointly presented on their experiences making acrylic resin fills with Paraloid B-72, an acrylic co-polymer, for use with glass repair. They based their work on techniques previously established by Steve Koob from the Corning Museum of Glass and recently updated at the CCI Symposium in 2011 (See here for the last update: https://www.cci-icc.gc.ca/discovercci-decouvriricc/PDFs/Paper%2035%20-%20Koob%20et%20al.%20-%20English.pdf).
Cutajar and Bristow treated two archaeological glass vessels: one Sassanian glass from UCL, and one beaker from Exeter, as case studies. They had common goals of needing reconstruction, stabilization, and the ability to be studied. They also had similar physical characteristics of degraded but stable glass with relatively good contact between the extant shards, thin walls (as thin as 0.2 mm), and substantive loss around of 35%.
Detail of resin fill in place on the Exeter glass jug (300/1988/G155, Royal Albert Memorial Museum, 2015). Photo by Hana Bristow
In looking for a fill system, they wanted a material that could reinforce weak areas, aid in practical assembly, and be as minimally interventive as possible. Since working with epoxy would require considerable manipulations with the artifact for both direct and indirect casting methods, this was not chosen. Instead, acrylic resin fills were explored because they are lightweight, strong, flexible, thin, detachable for future retreatment, simple to produce and insert, and can be manipulated for color and opacity matching.
Detail of resin tab application on Sassanid glass vessel (6300, UCL Conservation Teaching Collection, 2015), highlighted on the left and blended against the glass on the right. Photo by Jan Cutajar.
Koob’s technique is based on 30% w/v Paraloid B-72, an acrylic co-polymer, in acetone, with ethanol added to slow the evaporation rate, thereby reducing the potential for bubble formation. For coloring, ground pigment can be added to the ethanol before adding it to the resin mixture. The pigmented ethanol should be first decanted to prevent larger pigment particles from being added. The solution is cast and stored in a partially sealed environment for slow evaporation. Bristow felt that B-72 alone was too flexible, so she explored resin mixtures and tested varied proportions using B-72, B-48N or B-44 either straight or mixed in 2:1 ratios but always 30% in acetone. She also tested these opacifiers: fumed silica, marble dust, titanium dioxide and whiting. She cast the test resin mixtures in boxes of the same size, also holding the volume and concentration of the solution and the volume of added ethanol constant. The tests were evaluated after 4-5 days of curing for hardness, plasticity, and appearance. She found that a 2: 1 solution of B-72: B-48N produces a strong film without brittleness. This film was stronger than the B-72 film and not brittle like the B-48N alone or B-44 films.
The resin films are set to cure in a partially sealed solvent atmosphere. Photo by Hana Bristow.
For the opacifiers, Bristow found that fumed silica worked well for adding translucency, and marble for opacity, but whiting and titanium dioxide produced speckled results and were difficult to homogenize with the mixture. She also notes that dry artist pigments are good for tinting but shouldn’t be relied on for opacity as well, because they easily over saturate the mixture, resulting in a cracked and weakened cast. She recommends a maximum of 1.5 micro-spatula scoops per 30 mL resin mix.
Cutajar and Bristow offer some practical notes and tips:
Achieving desired film thickness can require some trial and error. Expect about 70% volume shrinkage.
Trays should be non-absorbent and easily release the resin. Making or using solvent-resistant boxes lined with release papers or films works well.
Enclose the poured resin trays in an acetone rich environment to slow the rate of evaporation. This will help prevent bubble formation.
Films should set for at least 4-5 days before removing, otherwise the films are too flimsy for these applications.
Films are best to manipulate directly after demolding. Things that can be done are:
Texturing
Shaping
Cutting – determine the size by taking a tracing of the loss area
Shape can be adjusted using heat; about 20 seconds under a hair dryer works well. Once warm, hold the cast in the desired position until it cools enough to hold the new shape. This can be done through repeated heating and cooling cycles until desired shape is achieved.
Adapt a cast by creating a lip at the edges where joins are very thin. This creates a slight overlap with the adjacent glass. The lip can be created with a heated spatula away from the glass.
Bonding can be activated with acetone, but Cutajar and Bristow suggest using more adhesive (Paraloid B-72) to make the join since acetone can compromise a good fit.
The film can be cut into tabs and used as reinforcements across joins. Cut the tabs into shape, lay them across the join, and activate with solvent. The tabs are virtually invisible.
The film can be used to make recessed fills for backing thin, curved glass, providing local stabilization and weight redistribution.
Backing films are easier to apply when they are freshly removed from the solvent atmosphere and retain a slight tack.
Paula Artal-Isbrand, Objects Conservator at the Worcester Art Museum, presented the various ways in which she uses paper in her objects treatments. She shared some background on paper types. Asian papers typically come from the paper mulberry tree and produce long fibers (kozo) and strong paper or from the gampi tree, producing shorter fibers to make crisp and translucent papers. Mitsumata shrubs are a third source, but not part of this presentation. Western papers are more often made from cotton, linen, flax, or hemp. Paper in conservation is strong, inert, compatible with conservation materials, has excellent long-term stability, and does not pose health risks. It can also be manipulated to mimic a wide range of materials through inpainting and coating. By choosing the right coating materials, the translucency and texture can be adjusted to fit the application. These papers can also be inpainted with standard inpainting materials to match color and texture.
Beaker, Roman, 3-5th century CE, glass, 15.5 x 7.0 x 6.5 cm. Sardis archaeological site (Turkey), Inv. # AhT67.IV.130N3,before and during treatment using kozo paper saturated with B-72 acrylic consolidant (Courtesy of Sardis Archaeological Excavation, photo: Paula Artal-Isbrand)
Artal-Isbrand outlined two ways for thinking about how to use paper. First, it can be used as a restoration material. Artal-Isbrand offered several examples of how she’s used paper in this way. For example, she used acid-free matboard cut into shape for a loss repair in a fan. For archaeological glass, she toned paper kozo paper with watercolors (not with acrylics since they would create too much opacity) and impregnated the paper with Paraloid B-72, acrylic co-polymer. The toned and resin soaked fill was a perfect match for the glass and was attached with Paraloid B-72. She has made paper fills to reconstruct chain mail, for joining heavy elements of an iron helmet, for reinforcing failing solder joins for bronze armor, and for backing a Roman lead curse tablet that needed to be unrolled. These repairs were carried out using a combination of kozo paper with Paraloid B-72, and are a testament to the paper’s strength. Artal-Isbrand also described that paper can be an interlayer between an artifact and fill material to ensure reversibility and how cellulose powder can be a bulking additive for fills, and if toasted, can also impart pigment to fills.
Missyurka turban helmet, Ottoman Empire or Caucasus, 16th century, iron, 29 x 18 x 18 cm. Worcester Art Museum, 2014.102. Bequest of John A. Higgins, during and after treatment with kozo paper strips. (Courtesy of Paula Artal-Isbrand)Missyurka turban helmet, Ottoman Empire or Caucasus, 16th century, iron, 29 x 18 x 18 cm. Worcester Art Museum, 2014.102. Bequest of John A. Higgins, before, during (using kozo paper band-aids) and after treatment. (Courtesy of Paula Artal-Isbrand)
Second, paper can also be used as a tool. It can work well as a facing for an intermediate phase of treatment. It can also serve as a barrier layer. For example, thin papers are a great barrier film for gels. Here, Artal-Isbrand mentioned that thin gampi paper can be good for this. The paper is placed between the surface and the gel, allowing for easier clean up in gel removal. Paper can be a poultice material. Artal-Isbrand uses Whatman cellulose powder, which will cling well and hold the poultice solvent. For these same reasons, shredded filter paper soaked and blended in water can be used to create a mold of another artifact. The mold should be sealed with resin (for example, Paraloid B-72) to keep it from getting damaged by water applications. If using the mold for creating a plaster fill, this step is critical.
During the question / answer period, there was a brief discussion on how shredded paper serves well for poulticing, and is better than cellulose powder or other very fine materials, because those become difficult to remove and can leave a hazy residue. So, it is important to distinguish between powder and pulp or shredded and/or ground paper. An interleaving layer can be helpful if powder is used. Also during the discussion, another example was mentioned that paper can be rolled into “worms,” impregnated with Paraloid B-72, and inserted it into losses to provide filling that is more easily removed than putties or other fillers.
The Textile Specialty Group audience got a real treat with Dana Goodin’s talk on using agarose gels on tapestries. Dana, who works at the Textile Conservation Laboratory at the Cathedral of St. John the Divine in NYC, used agarose gel on two tapestries in two different ways.
The first was a Baumgarten tapestry dating to the 1910s. It, and many others, were discovered on the walls of a townhouse on the Upper West Side of Manhattan after a developer purchased the property. In previous years, the room the tapestries were in had been rented out as a studio apartment. (As an NYC resident myself, you can only imagine the envy this inspired in me!) The tapestries were attached to the wall around the perimeter with nails. Stains from leeching plaster were prevalent and the lining had fallen down behind one tapestry, resulting in ballooning and a large slit at the bottom. A square had even been cut out of a tapestry to access a utility box! The tapestries were de-installed in 2013 and brought to the Lab, where there were laid flat in a humidity tent. The humidity was maintained between 52% – 58% for many months. This was not enough, however, to restore flexibility to the desiccated silk elements of the tapestry. Since the silk in the tapestry was in such poor shape, it was feared it would disintegrate during wet cleaning. It was therefore decided to clean, and of course humidify, the tapestries through agarose gel. Dana told us that the Textile Conservation Lab would usually use a 1% density gel if the material were smooth and could later be rinsed under suction. Because this was not an option with the silk, it was decided to also rinse the cleaned tapestry with agarose gel and deionized water. For cleaning, 3.4% density gel, ¼” in thickness, was cast with Orvus. The Orvus solution was 5ml to 300ml water. The entire Baumgarten tapestry was cleaned with gel, although the wool elements received thicker gels and were rinsed under suction, rather than with gel. The treatment was a great success: the appearance was incredibly improved and the tapestry regained enough moisture that it could afterwards be rolled without worry.
Clearly, this treatment required a lot of agarose gel, the cost of which escalated quickly. Not to mention the time spent casting it. Therefore, Dana and the other conservators at the Lab tried out reusing the gels. Tests were performed on white China silk and it was found that after three rinses/soaks of the gels in Orvus, no soiling was redeposited on the test silk. This was a great find, although it was concurrently found that the gels could only be reused three times before disintegrating.
The second tapestry Dana spoke about was an Agam tapestry from the 1970s. It was made from white wool yarn and a variety of wool/synthetic colored yarns. It suffered from hard glue residue on the top and bottom 2” of the tapestry, which previously attached a lining. Complications arose from the fact that the red and black yarns bled. The face of the tapestry was cleaned via dry surface sponging, but obviously that did nothing to address the glue, which was so hard it couldn’t be sewn through. Tests showed that amyl acetate removed most of the glue. Application methods tested were with blotters, cotton linters, and agarose gel. The agarose gel proved the most effective. Gauze was placed below the tapestry, then the gel was draped over the glue, before being weighted. Although effective, this proved very time consuming. To speed things up, Dana and the other conservators decided to apply the amyl acetate directly to the glue and then drape the gel over these sections with weights on top. 2% gel was used for this, and left on for one hour. This process was repeated until as much glue was removed as possible. The treated areas were rinsed with deionized water, and the tapestry received a new lining and a Velcro hanging mechanism.
I don’t think I’m overstating things by saying these were two awesome treatments. Thanks for sharing them with us, Dana!
