Gels in Conservation Conference, October 16-18, 2017
This blog post is part of a series of observations about the London “Gels in Conservation” conference co-hosted by the Tate and IAP (International Academic Projects, Ltd). In mid-October, over the course of three days, some 41 authors presented research, techniques and ideas on gels in conservation. The talks were excellent, and I’ve focused on four that were notable for the wide range of materials treated and challenges faced. They ranged from coating/grime removal from a giant sequoia tree cross section, to dirt and varnish removal from Delacroix wall paintings, to removal of repairs from a fragile felt hat from a 18th century ship wreck, and an experiment comparing residues left behind by various gels on paper.
2. Image of felt hat during treatment using gel and spider tissue to remove old repair.
Jonathan Clark’s presentation, “Revisiting a shipwrecked felt hat for Chatham Historic Dockyard Trust: a multidisciplinary approach” featured a really cool felt hat from a 1758 shipwreck. The project resulted in an unusual opportunity for collaboration between a textile and an objects conservator–both bringing needed experience to successfully treat the hat. In the past, the object had been treated aggressively with layers of synthetic materials and heavy cardboard fills. The hat was misshapen as a result of the thick repairs, making it difficult to fully see the original object. The treatment objective was to release the fragile felt hat from its past repairs and reshape it to its intended form without harming the object. Acetone softened the thick unknown adhesive, so both acetone vapor and solvent gels were used to release and reduce the adhesive. The acetone solvent gel was applied through spider tissue, a very soft and strong paper (100% manila fibers). Once in place, the spider tissue was pre-wetted with methylated spirits, then the gel was applied via spatula, which was then covered with plastic wrap to slow evaporation. Once the old repairs were removed the hat remained misshapen, to further soften the remaining adhesive holding the felt hat out of shape, it was placed in an acetone vapor environment. The softened pliable hat was then weighted and pinned to a Fosshape form, a shrinkable polyester felt, used by textile conservators to create mounts. The end result was an object that was stable and could safely be stored showing only its original materials.
Felt hat after treatment pinned to Fosshape form.
This blog series is a result of receiving the FAIC Carolyn Horton grant to help me attend the conference. I would like to gratefully acknowledge the FAIC for helping make it possible for me to attend this important conference.
There are 4 (four) available spots to attend the two-day workshop on “New products for Pressure Sensitive Tape removal” in Barcelona, Spain.
The workshop is part of the dissemination plan of the Nanorestart project (H2020 Grant Agreement 646063) and therefore has no cost for the participants except for travel and accommodation. It will take place on May 16-17, 2018 and will be taught in English by the paper conservator Antonio Mirabile.
Preference will be given to University Professors that teach in a recognized Master in Conservation in Europe so that they can disseminate the new knowledge gained. If none applies, then paper conservators working in institutions with large conservation sections across Europe will be considered.
Those interested should send an email to consrestpat@ub.edu with the subject “PST workshop” and the following information:
If you are a University Professor:
Name:
Surname:
Job title:
University:
Master’s name:
Master’s web page:
Unit currently taught:
City:
Country:
Studies done (at Bachelor/Master/PhD level) indicating type, title, year and university:
If you work somewhere else:
Name:
Surname:
Job title:
Institution:
Conservation speciality:
Number of conservators working in your institution (all specialities):
City:
Country:
Studies done (at Bachelor/Master/PhD level) indicating type, title, year and university:
More details on the workshop can be given upon expression of interest in the course.
Archiving 2018: Digitization Preservation, and Access
April 17-20, 2018
National Archives, Washington, DC
The IS&T Archiving 2018 conference will explore the digitization, preservation, and access to 2D, 3D, and AV materials through a blend of short courses, invited focal papers, keynote talks, and peer-reviewed oral and interactive display presentations, behind-the-scenes tours – all to provide participants with a unique opportunity to gain and exchange knowledge and build networks among professionals.
Program topics: Spectral Imaging • Imaging Performance • Digital Archiving • RTI • 3D Photogrammetry • Quality Assurance Workflows • Color Measurement • Metadata and Workflows • Multispectral • Cultural Image Capture
Registration includes the technical program April 18-20 and the conference proceedings
Can’t attend the full week of #Archiving 2018? Select the day that best accommodates your interests.
Discounts for registering for 3+ Short Course
Group rates available for 5+ registrants from the same institution. Contact IS&T directly.
Early access to Behind-the-scenes tours. Details released first to participants registered by March 18
Not a member? Include IS&T membership (new or renewal) with your registration along with an online subscription to the Journal of Imaging Science and Technology (JIST) or Journal of Electronic Imaging (JEI) — all for the same price as the non-member registration rate.
This blog post is part of a series of observations about the London “Gels in Conservation” conference co-hosted by the Tate and IAP (International Academic Projects, Ltd). In mid-October, over the course of three days, some 41 authors presented research, techniques and ideas on gels in conservation. The talks were excellent, and I’ve focused on four that were notable for the wide range of materials treated and challenges faced. They ranged from coating/grime removal from a giant sequoia tree cross section, to dirt and varnish removal from Delacroix wall paintings, to removal of repairs from a fragile felt hat from a 18th century ship wreck, and an experiment comparing residues left behind by various gels on paper.
In the second of four talks, Alina Moskalik-Detalle presented “Conservation of murals by Eugene Delacroix at Saint Sulpice, Paris.” The talk was interesting for its scale and challenges. Because I’ve gone to see these murals many times over the years, the talk was also personally interesting. Each time I visited, I left somewhat disappointed by the darkened, flat, dull murals. As luck would have it, I was scheduled to travel to Paris a week after attending the gels conference. What I saw when I visited Ste. Sulpice was truly remarkable—color, depth, and drama. The cleaning had totally transformed these murals. Naturally, I couldn’t help myself, I actively looked for shiny patches—the results from this treatment were remarkable. This multi-year project involved numerous conservators including collaboration with Richard Wolbers. Some of the treatment challenges included flaking paint, complex paint layers, multiple restorations, rising damp in the walls, carbon based grime, and, if that wasn’t enough, the paint was very sensitive to organic solvents. The conservators wanted to limit penetration of their solvent gels without leaving a residue or tide line behind. They wanted good contact between the gels and the substrate, control of the action of water, and to create mixtures of solvents that would clean effectively without damaging the paint layers. After cleaning tests were performed, a treatment protocol emerged: by pre-saturation of the areas being treated with cyclomethicone followed by the application of silicone solvents gels to the mural’s surfaces, tide lines were avoided, grime could be removed, the gels could be cleared, and residue was limited. The D4 was a slow evaporator which allowed about a 30 minute working time for the application of the gel and subsequent grime removal without harming the paint layer.
3. Delacroix mural detail, during treatment
The gels were made and applied in a paste-like consistency for maximum control of where the material was placed. It clung to the vertical walls and horizontal ceiling long enough to be effective. Using D4 based emulsions to clean the mural’s paint surfaces allowed the removal of surface soil without stripping wax or oily components from the paint films themselves. Because the emulsions were surfactant free, it was easier to clear them from the treated surfaces. Analysis of samples didn’t show residue left behind on the surface, but when the conservators tried to consolidate flaking areas of paint, they had trouble with adhesion, it is unclear why. It will be interesting to see how these murals age over time and if further treatment is needed in future, how re-treatable it is.
4. Author pictured in Delacroix chapel after treatment was completed.
This blog series is a result of receiving the FAIC Carolyn Horton grant to help me attend the conference. I would like to gratefully acknowledge the FAIC for helping make it possible for me to attend this important conference.
This blog post is part of a series of observations about the London “Gels in Conservation” conference co-hosted by the Tate and IAP (International Academic Projects, Ltd). In mid-October, over the course of three days, some 41 authors presented research, techniques and ideas on gels in conservation. The talks were excellent, and I’ve focused on four that were notable for the wide range of materials treated and challenges faced. They ranged from coating/grime removal from a giant sequoia tree cross section, to dirt and varnish removal from Delacroix wall paintings, to removal of repairs from a fragile felt hat from a 18th century ship wreck, and an experiment comparing residues left behind by various gels on paper.
Giant sequoia section displayed in the central hall of the Natural History Museum
The first session of four, “Giant sequoia: an extraordinary case study involving Carbopol gel”, was presented by Lu Allington-Jones and was intriguing for several reasons: the object was enormous–5 meters (over 16 feet) in diameter. The size alone produced significant challenges, for which solvent gel was particularly suited. The scale meant that it would be treated in situ in full view of the public, thus potentially exposing patrons to chemical fumes; it would require large amounts of materials to treat; and it was at the top of an open staircase, meaning significant height came into play, as well. The giant sequoia cross-section had been on continual display since 1894, so it was incredibly dusty, had a darkened and cracking lacquer coating, and had a very friable bark around its perimeter. A material was needed that could safely remove the failed coatings and accumulated dust without penetrating the surface, harming the friable bark, or creating an unsafe environment for the conservators and patrons during treatment. Using a solvent gel had the advantage of keeping the solvents contained, reducing solvent vapor, and could act as a poultice to reduce grime and solubilize the failed coating. In addition, because gel ensures contact with the treated surface, it means that a lower concentration of solvent could be used as compared to a free liquid solvent. The gel was made 24 hours ahead in Ziploc baggies, the time allowed the gel to reach the needed smoothness and viscosity.
Applying solvent gel from plastic baggie (left). Removing solvent gel after treatment (right).
For application, the Ziploc bags were cut open at one end, the gel squeezed out and spread to 20 mm thick (about ¾”), then covered with plastic wrap to slow evaporation, giving the conservator about an hour of working time before the gel became too sticky and unworkable. Once the gel softened the coating, it was then removed trowel-like with a piece of cardboard, repeated, then cleared with industrial methylated spirits and wipes. A significant lesson learned about the gel was once it reached 73F or more, it became runny, causing the gel to slip off the vertical surfaces being treated, which didn’t allow enough working time to reduce the surface coating adequately. Once treated, the cross section was varnished with a protective layer of Laropal A81. The cross section looked amazing in the after images. I would encourage everyone to read the article in the post prints as it describes the details of challenges, decision making, and final outcomes.
This blog series is a result of receiving the FAIC Carolyn Horton grant to help me attend the conference. I would like to gratefully acknowledge the FAIC for helping make it possible for me to attend this important conference.
This blog post is the 2nd in a collection of observations about the London “Gels in Conservation” conference co-hosted by the Tate and IAP (International Academic Projects, Ltd). In mid-October, over the course of three days, some 41 authors presented research, techniques and ideas on gels in conservation. The first presentations of the first day kicked off the conference, setting the tone with intriguing philosophical, as well as practical hands-on examples of gels in conservation. The two leading conservation scientists in the field of gels, Richard Wolbers and Paolo Cremonesi, each provided an introduction to gels in conservation, what has been done historically, what is currently practiced, and thoughts for the future. Wolbers not only delivered the key note presentation, but spoke several times as collaborator for many of the talks and as a moderator. In his keynote address, Wolbers emphasized minimizing toxicity through substitution of less toxic materials and Cremonesi discussed the characteristics of agar gels and the current work being done with thermo-reversible rigid agar hydrogels.
Bottom line, it seems that the basic goal for many of the case studies that were presented is to find a way to safely use aqueous cleaning systems on water-sensitive materials without damaging the object. A tall order.
Richard Wolbers, keynote presentation, “Gels, Green Chemistry, Gurus and Guides”
Wolbers’ talk, “Gels, Green Chemistry, Gurus and Guides”, it provided an overview of gels in conservation, as well as a look towards the future, emphasized the goal of using Green chemistry, which involves less waste and is less toxic – something he has been advocating for years (here is the link to his talk: https://www.youtube.com/watch?v=RGpOYaU6owE).
Wolbers said, when confronted with a treatment problem, first determine if a gel is appropriate. Gels keep the gel and its contents in contact longer with the surface; gels make local application controllable or they can serve as a poultice. Naturally, the gel used shouldn’t impact the surface medium, and it should be non-toxic and clean the object. Wolbers listed some of the advantages of solid rigid agar gels: they dissolve in water, improve surface wettability, and have surfactant properties.
Ultimately, to do the best by our objects, we as a field need to continually look to other industries for ideas. For example, the cosmetic industry utilizes green chemistry to reduce exposure to potentially harmful solvents. We need to truly understand what we want to achieve in a particular circumstance and tailor it to our object, rather than relying on a few stock recipes and applying them to all situations. As conservators we must remain agile and stay creative. To do this we must understand the underlying principles of the materials we want to use and the objects we are treating. Conservation needs to be able to gain ideas and experience from other fields, and also be able to create and engineer our own materials to give us the type of control we need.
Paolo Cremonesi, “Thermo-reversible rigid agar hydrogels: their properties and action in cleaning”
In Cremonesi’s talk, “Thermo-reversible rigid agar hydrogels: their properties and action in cleaning”, (here is the link to Cremonesi’s talk, https://www.youtube.com/watch?time_continue=10&v=UbbxCQR4El8) he listed the advantages of agar gels: how they dissolve in water, and improve surface wettability. They have limited adhesion to the surface and, most importantly, leave behind minimal residue (as compared to gellan gum. (See M. Sullivan’s paper “Rigid polysaccharide gels for paper conservation: a residue study”). Past drawbacks of agar gels had been that they could only be applied to relatively flat surfaces. However, if the liquid gel is applied (brushed or poured on) just at the moment it starts to thicken, it can be used on a variety of surfaces, planar or not.
Thermo-reversible gels are often prepared in the microwave to prepare a homogeneous gel. When heated above 80F (Cremonesi recommended type E for its low gelling temperature) the gel is liquid and when cooled below 80F it is a solid. With increased concentration, the gel becomes stiffer which will slow the release of water from the gel. While in the liquid form it can be poured into receptacles such as a syringe body. Allowed to cool, once solid it can be kept in a “pencil” shape (this slide caused many audience members to swoon) or be cut into small plugs.
slide from Cremonesi’s presentation, grating agar plugs
At room temperature it can also be grated, with the shaving manipulated for surface cleaning. Enzymes mixed with Agar in a semi-solid state are the most effective form of the material. That said, Cremonesi said gellan gum is more appropriate for works on paper because it’s more flexible and transparent than agar.
One thing I’ve found with using gels (in my case gellan gum) is the formation of tide lines, which made me assume we were doing something wrong. According to both Wolbers and Cremonesi, I was missing a step. They talked about the importance of pre-wetting the surface to be treated with a non-polar solvent (they specifically mentioned D5, aka decamethylcyclopentasiloxane aka cyclomethicone). At first this might seem counter-intuitive: how does water work if there’s non-polar solvent in the way? Actually it’s about displacement – oil floats on water – so the water in the gel displaces the non-polar solvent to get to the surface. The non-polar solvent prevents tidelines principally by blocking capillarity. Now it’s all starting to make sense. The same principle was used by Burgio, Rivers et al (2008, Studies in Conservation) when consolidating matte paint. On this basis, any non-polar solvent (first spot tested) should work to prevent tidelines. D5 has the advantage of being a ‘green’ solvent, comes without the H&S hazards associated with hydrocarbon non-polar solvents, and is exceptionally non-polar.
This blog series is a result of receiving the FAIC Carolyn Horton grant to help me attend the conference. I would like to gratefully acknowledge the FAIC for helping make it possible for me to attend this important conference.
A couple of months have passed since I attended the London three-day conference “Gels in Conservation” co-hosted by the Tate and IAP (International Academic Projects, Ltd), better known as James (Jim) Black. You will know him from Archetype Publications; he’s the one who always remembers you.
Gels conference audience
The conference was the brainchild of Jim Black and Richard Wolbers, hatched over drinks and Indian food a few years back. They posed the idea, “wouldn’t it be great if we got all the people together working in gels? Scientists, conservators, students, etc., and shared what we know, or were working on in gels?” Apparently they were right, they weren’t they only ones who thought it was a great idea. More than 550 attendees from 39 countries attended the three-day conference. For me, and judging from fellow attendee’s responses, I can tell you it sure felt like a roaring success.
It was one of the most thoughtfully arranged symposiums I’ve ever attended. I suspect Jim Black may well be a genius and I hope other program organizers take note. There were three sessions each day, and each session started off with two or three talks about 25 or 30 minutes in length followed by several 10-minute talks. It kept things fresh and helped avoid listening fatigue. For the most part the 10-minute talks were just as informative as the longer format. At the end of each session the presenters had a panel Q&A with the audience. This gave people a chance to clarify and presenters an opportunity to add detail.
The conference was filmed/recorded, so take heart even if you didn’t get one of the sought-after tickets: you can still virtually attend, albeit slightly after the fact. Having the publication at the conference was brilliant. I can’t emphasize enough how excellent the publication is. It includes the papers from the presentations and the posters with great images. It was very helpful to listen to a talk then be able to refer to the paper immediately. Over the course of three days, some 41 authors presented research, techniques and ideas. Each day the talks were grouped together loosely by theme such as polysaccharide gel systems, which included agars, gellan gum and methyl cellulose, often compared or alone, sometimes with additives like enzymes or chelators. Day two, polysaccharide and polyacrylic gel systems, which included solvent gels, such as pemulen, and the new wave of solvents, silicone solvents. And finally, day three was entitled Novel and Multi gel treatment. Many speakers talked about trying to utilize less toxic materials as an alternative to “traditional” organic and aromatic solvents, moving toward greener alternatives. Authors shared their successes and failures, both being very informative. Many attendees, me included remarked that they really enjoyed the multi-discipline approach, learning what textile conservators and easel painting conservators are doing with the same sort of materials. It was very inspiring and informative.
The overall tone of the conference was one of hopeful optimism and desire for more research and development. Richard Wolbers spoke several times, first as the key note speaker and later as collaborator for many of the authors. He emphasized the need for conservators to look to other industries for potential products, greener or less toxic than what we use now, and to know the materials well enough to tailor them to our own specific needs for each specific treatment challenge. I came away inspired and intrigued. I have written companion blogs to this one and they will be posted in rapid succession. I hope I can convey some of what I learned and inspire you to obtain the publication and start reading. I will end with my favorite slide of the conference.
Your Plan vs. Reality.
This blog series is a result of receiving the FAIC Carolyn Horton grant to help me attend the conference. I would like to gratefully acknowledge the FAIC for helping make it possible for me to attend this important conference.
My session co-chair, Glenn Corbett, and I are are seeking abstract submissions for the Cultural Heritage Management session(s) of the American Schools of Oriental Research annual meeting, which will be held in Denver, Colorado, November 14-17, 2018. This session welcomes papers concerning all aspects of archaeological conservation and heritage management in areas throughout the Near East. For the 2018 meeting, we are especially interested in presentations focusing on:
conservation and preservation activities
engagement and education of local communities (including topics involving site museums and visitors’ centers)
site management planning
Interested speakers should submit a title and abstract (max. 250 words) by February 15, 2018. Please see ASOR’s call for papers and instructions for submission here: http://www.asor.org/am/2018-call-for-papers/.
You may send inquiries or questions to Suzanne Davis (davissL@umich.edu) and Glenn Corbett (joeycorbett@yahoo.com). Please consider submitting! The ASOR annual meeting is primarily attended by archaeologists, and it is a wonderful venue for professional outreach about archaeological conservation.
NANOTECHNOLOGIES FOR CONSERVATION OF CULTURAL HERITAGE AT PRATT INSTITUTE : A hands-on workshop available to midcareer conservators
Professors Piero Baglioni and Rodorico Giorgi from the University of Florence Center for Colloid and Surface Science (CSGI) will present nanostructured dispersions such as nanoparticles for consolidation, micellar solutions, microemulsions, and responsive gel formulations including chemical gels, physical gels and organo gels. Through lectures and lab demonstrations participants will learn the chemistry, theory and application of each system. Participants will carry out various excercizes using mockups, sculptures, paintings and works on paper. Participants are also encouraged to bring their own objects and materials for tests and discussion during the last day of review and open labwork. (A daily outline for the workshop is available upon request).
PIERO BAGLIONI received his PhD from the University of Florence in 1977 and is a Full Professor of Physical Chemistry at the Department of Chemistry and CSGI of the University of Florence. He is the author of over 250 publications in the field of colloids and interfaces and pioneered the application of soft matter to the conservation of cultural heritage. He has lectured world wide and he has produced several innovative methodologies
RODORICO GIORGI received his PhD from the University of Florence in 2000 and is currently a Permanent Researcher at the Department of Chemistry and CSGI of the University of Florence. He is the author of 60 publications in the field of conservation of cultural heritage materials. His background is in the physical chemistry of colloid and interface science and in the last decade he extended his activity on the application of nanotechnology to the conservation of cultural heritage.
WORKSHOP DATES: February 12-19, 2018
WORKSHOP HOST: Department of Math and Science, Pratt Institute
LOCATION: Pratt Institute, 200 Willoughby Avenue, Brooklyn, NY, Department of Math and Science
ORGANIZERS: Cindie Kehlet ckehlet@pratt.edu
Sarah Nunberg snunberg@pratt.edu
Soraya Alcala soraya.alcala@gmail.com
ADMISSION: Applicants are requested to submit a statement on the applicability of the course to their work, and a brief cv listing their relevant education and employment background.
Please e-mail your application to snunberg@pratt.edu and enter CSGI Workshop 2018 in the subject line.
APPLICATION DEADLINE: December 1, 2017
WORKSHOP COST: $500.00
TRAVEL AND HOUSING: Participants are responsible for their own travel, meals, and housing arrangements. Recommendations for moderately priced accommodations are included with acceptance packets.
Workshop 2 GETTING STARTED: A SHARED RESPONSIBILITY
CARING FOR TIME-BASED MEDIA ARTWORKS IN COLLECTIONS
Monday, June 11 – Friday, June 15, 2018 at The Museum of Modern Art, NY
Does your institution have a collection of time-based media artworks in need of a long-term preservation plan? Are you uncertain where to get started? This five-day hands-on workshop will provide an in-depth overview of the processes and workflows which can be implemented at collections without dedicated time-based media conservators. Participants will leave with the knowledge and tools to design and execute action plans at their institutions.
Caring for time-based media art collections is widely acknowledged as a pan-institutional endeavor requiring direct involvement from curatorial, conservation, audio visual, IT, registration and collection care staff. This collaboration will be reflected throughout the curriculum as well as in the workshop application itself which requires a pair of colleagues from each applying institution. This workshop specifically requires that a curator and collection care specialist apply together as these positions have the expertise and authority to advocate for proper collection stewardship. The curriculum will cover activities pertaining to acquiring, exhibiting, installing, documenting, and advocating for media artworks.
Requirements for Application: This workshop is open to pairs of applicants: one curator and one conservator/collection care staff member (conservator, audio visual technician, collection specialist or manager, etc.) directly responsible for the care of the time-based media art collection. Priority will be given to institutions who are actively acquiring, with mid-sized media artwork collections that have significant needs, and require in-house staff training. Participants are expected to attend the full week-long program.
How to Apply: Applicants must provide a joint letter of interest (1,000 words maximum), and one letter of institutional support from the Director, or equivalent level. Co-applicants must be permanent members of staff (full or part-time) and each must provide a CV. Additionally, applicants must complete one online Collection Data Form. Applications which do not meet all requested requirements will not be considered.
The letter of interest must include: 1) why participation in this workshop is important to the collection; 2) a brief history of the media art collection; 3) candidates’ work with the media art collection to date; 4) how this workshop directly applies to applicants’ day-to-day work; 5) evidence of institutional commitment such as working groups, any specific initiatives or surveys, and demonstrable institutional desire to take action; and 6) prior experience with the topic or lack thereof as well as any relevant conferences or workshops attended on related topics.
Travel and lodging expenses may be reimbursed, based on need. Please submit a basic budget of anticipated costs as part of the application. There is no fee for this workshop; English will be the language of instruction. Applications should be submitted to allison_spangler@mona.org no later than January 16, 2018 with notifications expected by early to mid March. For more information: www.mediaconservation.io.
This workshop is part of The Museum of Modern Art’s Media Conservation Initiative, generously funded by The Andrew W. Mellon Foundation. The Media Conservation Initiative seeks to advance new strategies for the field of time-based media art preservation and restoration.
