Tag: AIC’s 40th Annual Meeting

AIC’s 40th Annual Meeting – RATS morning session, May 10, “Atomic Layer Deposition (ALD) films as protective coatings for silver”, by Amy Marquardt, Glenn Gates, Eric Breitung, Richard Ash, Gary Robloff, Ray Phaneuf, and Terry Drayman-Weisser*

*nb: the title of this talk, the author list, and author order all changed from what was published in the program. If I have left out an author name, I apologize.

The focus of this talk was to discuss the application of atomic layer deposited films of aluminum oxide (Al2O3) onto sterling silver surfaces. Ultimately, it is hoped that this process will be refined for use with sterling silver art objects in museums.

The overarching goals of this project are to find a coating for silver that is long lived; slows the diffusion of sulfur to the surface of the art object (I learned this fact at the presentation by Zeev Rosenzweig at the RATS luncheon); can be rapidly applied and covers the object homogeneously; is removable; and is less labor intensive than manual application and mechanical polishing.

(wow, that’s a lot!)

The University of Maryland has a “BENEQ TFS 500”, a commercially available atomic layer deposition (ALD) machine/instrument, to deposit thin film coatings on anything that is placed inside of it.
http://www.beneq.com/tfs-500.html

Awesome facts of this instrument:
• Samples placed in the instrument can touch one another and it won’t affect deposition;
• You can coat MANY samples all at the same time
• You can control the thickness of the layer you deposit onto the objects you place inside the instrument, down to the nanometer (nm) thicknesses
• Coatings are incredibly uniform
• The films made are dense (ie, tightly compacted), and these types of films make good vapor barriers
• Coating will go into very small crevices and tool marks
• Tailoring thickness allows you to control optical properties
• It can take a mere 1 hour to make a coating that is 100 nm thick

The project is currently examining whether aluminum oxide coatings perform better than nitrocellulose ones. They used accelerated aging studies (40°C, 30-50% RH, 20 ppm hydrogen sulfide pumped through a sealed chamber) on coated samples and performed Tarnish Rate Analysis (never heard of this!! measure color of tarnish; correlate to thickness of tarnish layer), X-ray photon spectroscopy (XPS), secondary ion mass time of flight mass spectrometry (SIMS-TOF), and atomic force microscopy (AFM) to analyze this.

RESULTS and CONCLUSIONS:
* A 80 nm aluminum oxide coating outperformed a microns thick nitrocellulose coating because it is more tarnish resistant than nitrocellulose.

* They said that that these results are very fresh and new but that the aluminum oxide coatings are removable with a minimal loss of surface copper and silver using dilute sodium hydroxide (NaOH) but that you have to be careful about the concentration of the NaOH because it can selectively remove copper over silver from the sterling silver alloy itself. But that we should all relax because the amount of copper or silver being removed is on the nanoscale.

Q&A session:

Comment: Eric presented removability study with weak NaOH compared to data from Glenn (I don’t know if this work is published or has been presented elsewhere), who used three different chalks (all of which were in the lab);

Q: is this atomic layer deposition instrument expensive?

A reactor costs…$500K. BUT you can build one or buy the parts separate and assemble one yourself; not rocket science to build one; there is a place in Cambridge (MA? England?) that sells on for <$100K; you can make a homemade one for ~$50K

Q7: how long will coating last?

At least 20 years; a guess, no hard evidence

One facet of this project is to build coatings even better than aluminum oxide

TERRY Weissman: lot of the current results presented here are theorhetical; we will be getting into more of the conservation issues as time goes along;

Also, we knew that NaOH would affect the copper; but often times, art objects are already Cu depleted; We might find a better solvent in the future

AIC’s 40th Annual Meeting – RATS morning session, May 10, “Progress in the investigation of silicone rubbers and their residues”, by Kasey L. Hamilton, Adriana Rizzo, and Anna Serotta

The focus of this presentation was to address problems associated with the use of slow and quick setting silicone rubbers for objects conservation applications. The main problem is that silicone rubbers often leave behind liquid and solid residues on objects after they are used. While it may be possible to physically remove the solids, the liquid residues often result in the development of a stain on the surface of the object where the silicone rubber had been applied. The question becomes, what is the chemical make up of these stains and can they be removed using solvents?

Why are we using these silicone polymers in the first place?
• to make casts for recasting
• to allow you to see an image or tool marks inscribed into a object better than you can see them on the object itself (silicone rubbers are homogeneous in color while objects themselves may not be)
• to non-invasively investigate the surface topography of the artifact

The research project entailed selecting eight different silicone rubbers and applying them to a series of different surfaces (plaster discs, limestone, and glass). Following removal of the silicones, attenuated reflectance-fourier transform infrared spectroscopy (ATR-FTIR) was used to determine the chemical make up (O-Si-O and Si-CH3 bonds) and depth of penetration of the liquid residues left behind. Several types of mass spectrometry (evolved gas, pyrolysis gas chromatography [PYGC-MS]) were used to study the eight rubbers and the molecular weights of the materials that are excreted out of the silicone rubbers and left on the different substrates.

RESULTS AND CONCLUSIONS:

* Hexane can be used to remove some of the staining material. I wasn’t sure how this conclusion was drawn? Regardless, it was a better solvent than either methanol (or was it ethanol) for removing some of the residue.

* When residues were observed, the color of residue was related to the color of the mold/silicome material

* Residues are mainly high molecular weight (HMW) components of the silicone rubber and are in their polymeric form – this wasn’t necessarily an expected outcome but it was what was observed

* It wasn’t possible to do a quantitative comparison of the amount of residue left behind between different rubbers

* Slow setting silicone rubber is bad for porous surfaces and residues can penetrate up to 100 microns into the surface (depending on the porosity of the object)

* Given the same rubber, the amount of residue left behind is a function of the material its applied to (intuitive?)

*Siloxane residues are comparable for quick setting rubbers

*Residues maybe reduced, but it is unlikely that they are effectively removed even with non-polar solvents

* There were a couple of others, but future work is to see if barrier coatings (methylcellulose) will help prevent residue deposition.

COMMENTS made following the presentation:

Baltimore museum stopped using silicone rubbers years ago; using silicones on rubbers causes patinas to disappear – patinas were saturated with silicone residues; little bits of set silicone were stuck in interstices of porous surfaces;

• I was surprised – atr is not really ideal for depth of penetration analysis; I also don’t think you can examine an area smaller than 20 um wide; can be hard to measure depths of penetration very accurately)

Any idea how porous the plaster is? Gypsum plaster – can you measure porosity?

Made sure used same batch of plaster throughout the experiments

AIC’s 40th Annual Meeting, The Creation, Implementation, and Safety of Digitally Printed Fabrics in Textile Conservation: Where are We in 2012?, by Miriam Murphy

Author Miriam Murphy, Kress Conservation Fellow, Museum Conservation Institute, and National Museum of African History and Culture, Smithsonian Institution, presented a review of digital printing techniques and their use in textile conservation. This was a great refresher for colleagues who have not kept up with advances over the past decade, including your’s truly.

There are seven steps in producing digitally printed textiles. Step 1 is the digital capture, using scanner or camera. Often this is done by the conservator.

Step 2 is image processing, which is bet left to the printer in order to produce accurate results and avoid hair-tearing-out by the conservator.

Step 3 is color management, for which a color blanket is an essential tool. This is a full printout of colors on the chosen substrate, best compared to the source object in the same lighting as eventual display, ie the gallery or historic house. The small fee for this color blanket is well worth the investment.

Step 4 is the printing process. Although 600-700 dpi is available, 300 is usually plenty good. Printers can print up to 138″ wide and are often constrained only by the size of the image file.

Step 5 is choice of ink. Pigment based inks are the best choice because they require no pretreatment to the substrate and dry with heat. They are susceptible to breakdown in extreme light conditions and with abrasion and much washing. Dark colors can also be hard to achieve and contrast between adjacent dark colors is not always great. Museum conditions usually can accommodate these limitations.

Step 6 is choice of substrate. There are many, many available substrates, but cotton remains the best choice for museum applications. The weave structure of the original does not have to match because the image will provide this detail. Fabrics are available form the printer or from TestFabrics or Jacquard Inkjet Fabric Systems.

Step 7 is pre and post treatment assessment–I confess my notes are sketchy about this step.

If you are interested in speaking with digital print houses, Ms Murphy suggested several including Super Sampler, First2print, LTS Design Service Corp and Digifab, most of which are in NYC, I believe.

The benefits of digitally printed fabrics in museums has been outlined elsewhere, but highlights include quick turnaround, high resolution, and increasingly small dye runs. Why aren’t we all using this technology??!!

AIC’s 40th Annual Meeting, A Successful Treatment Method for Reducing Dye Bleed on a 19th-Century Sampler, by Katherine Sahmel and Laura Mina

Conservation of an 1832 Scottish sampler in the collection of the Philadelphia Museum of Art was begun by Winterthur student Katherine Sahmel while an intern at the PMA and continues with FIT student Laura Mina, the current intern.

This outstanding sampler is part of the Whitman collection and is notable not only for its design but also for its provenience and the existence of photographs of the main building depicted in the embroidery. Prior to acquisition, the sampler was apparently washed causing extensive bleeding of green and red dyes. It has not been exhibited due to this unfortunate condition.

The dyes were analyzed by Ken Sutherland using FTIR, identifying Indigo Carmine as the probable blue component of the fugitive green dye.

Initial tests to reduce the dye bleeding with standard solvents and surfactants were not fruitful so Ms Sahmel applied the modular cleaning system developed by Richard Wolbers. Tests on small samples of threads from the back of the sampler led to the choice of a combined cleaning solution of EDTA (ethylenediaminetetraacetate)1% and TEA (triethylanolamine) .5%.

This system for cleaning requires extended contact with the textile, minimal wetting, and protection of surrounding embroidery threads. Cyclododecane was applied to the front and back adjacent embroidery yarns. A poultice of cleaning solution in methyl cellulose was then prepared and applied to the dye bleed. After treatment the methyl cellulose was removed and flushed with revcerse osmosis water before drying the treated area under suction.

The pros to this treatment was successful removal of dye bleed with minimal effect on adjacent threads. Cons include difficulty in clearing the methyl cellulose poultice and the high ph of the cleaning solution on the wool threads. When Laura Mina took over the project she modified the poultice to use agaros gel, which is easily prepared and removed. The cleaning solution was adjusted to add more TEA.

This research has wise applications in textile conservation, and sampler conservation in ap[rticular. It is non hazardous and requires no fume hood. Stay tuned for an exhibit of the Whitman Samplers coming to the PMA.

AIC’s 40th Annual Meeting, Repair of 20th-Century Leavers Lace, by Annie-Beth Ellington

Lever’s Lace is a type of machine-made lace that provides a similar product to hand-made bobbin lace. Its structure and relatively low-status in museum collections have made it an uncommon target for conservation treatments. The author’s graduate thesis research for her MA at the University of Rhode Island both brings to light this historic textile and provides guidance in how to undertake stabilization of damaged samples.

In 1813 John Lever modified a loom to make Lever’s Lace, and subsequent addition of Jacquard technology in 1849 increased the range of the product. It was imported to the US in 1910 to make mosquito netting and other simple structures, eventually creating the decorative lace familiar to many people. Lever’s lace consists of a ground of twisted warps. Patterns or ornaments outlined by a heaver thread are accomplished with bobbins.

The author experimented with mock-ups of the structure to better understand the challenges of repairs. She then tensioned a piece of damaged lace over a black fabric-covered board. A photocopy of the pattern area was inserted beneath to act as a guide. Using a microscope, she floated 40 denier nylon threads across areas of loss following the pattern. The author quickly found that intervention could cause additional unraveling of damages areas, so she changed to using Jade adhesive on broken thread ends prior to repairs.

Repair of Levers Lace is slow and dyeing nylon thread to match colors would only add to the project time. However with further development this technique will guide future conservators.

AIC’s 40th Annual Meeting, Recovery and Conservation of the Textile Collections at the National Museum of Music, Alina Vazquez De Arazoza

Alina Vazquez de Arazoza is one of 20 Latin American colleagues who were able to join us at the 40th Annual AIC meeting thanks to funding from the Getty. Ms Vazquez requested that our colleague Amparo Ruedas read her paper to the TSG.

In 1971, a former Colonial mansion located in Havana was converted to the National Museum of Music. It contains, among its diverse collections, costumes of prominent Cuban musicians and banners from musical groups. The majority of collection dates to the 20th century, but several important 19th century items are also preserved. Among these is the glove of Perucheo Figueredo, the author of Cuba’s national anthem, and great great grandfather of Amparo Ruedas, giving added meaning to this presentation.

The renovation of the museum building provided the opportunity for the author to survey the collection, undertake conservation treatments prior to rehousing and exhibition, and do biographical research into the artists represented by the collection. She worked in collaboration with CENCREM (Centro Nacional de Conservacion, Restauracion y Museologia) which provided a facility and analytical assistance, all at no charge!

In general the collection was in fair condition. Items were dirty, distorted from poor storage, and dry, despite the tropical climate and lack of adequate environmental conditions. Humidity had taken a toll on some items, however, as seen by corroded metal trims, associated staining, some water damage with dye migration, and some insect damage. Much of the collection also exhibited yellowing.

The author undertook analysis of items in order to prepare a proposal for conservation. SEM results confirmed fiber content of organic and metal components. Much of the collection is hand made, though industrially produced items and commercial labels were noted and researched. The presence of prior repairs were documented, as well as types of adhesives that had been employed. Parameters of the conservation project were set out identify which textiles needed surface cleaning, aqueous or solvent cleaning, which prior repairs would be reversed.

What impressed me most about Ms Vazquez’s and her project are the advanced level of treatment skills, storage and conservation materials, analytical tools and connoisseurship compared to other parts of Latin America and the Caribbean that I have visited. This conservation project was equal in all ways to similar projects undertaken in the United States, which happily dispelled my notions of the ability of Cuban conservation professionals to achieve a high level of skill and accomplishments.

AIC’s 40th Annual Meeting- Objects and Research and Technical Studies Joint Session, May 9, 2012 “www.chemistryinart.org: Chemistry in Art Scholars– A Virtual & Real Community” by Hill and Odegaard

I’m not an educator, but while listening to this talk I was thinking “Sign Me Up!”. Dr. Hill spoke about the intensive workshop provided for educators who want to improve their science classes or start new ones. She’s a professor at Millersville University and wants conservators to know that chemistry professors are safe to connect with! The overarching program of cCWCS (Chemistry Collaborations, Workshops, and Communities of Scholars) covers many topics, but she focused on those that combine chemistry and art. You can check out their website (there was a typo in the original talk title) and find lots of materials if you aren’t able to attend the workshop or you’re just interested in finding out more about what they do. If you are thinking about starting a class or want to improve a class that you already give this 5-day intensive workshop might be for you. And it’s all expenses paid, thanks to the NSF. Their target audience is undergraduate faculty and staff and includes mainly chemists, practicing artists and art faculty. They are interested in having more representation from the conservation community. It sounds like a fun way to get the word out about what conservation is and what conservators do as there is a high degree of confusion about the difference between curators and conservators amongst this group. Also, you could potentially make some helpful contacts in the chemistry world.

The participants come from all over the country and generally fall into four categories:

  1. those how are looking for a fancy vacation (really a minority)
  2. older faculty who now have more flexibility in their schedule and are looking to pursue interests outside of their previous research and bring excitement to their students
  3. mid-career faculty who are looking for a unique area of research or trying to find their teaching niche
  4. and community college faculty who are looking for support and to bring interesting applications to students to engage them and get them more enthusiastic about science.

Vicki Cassman is an example of one of their alums who attended a session in 2010 and took what she learned back to UD for an honors seminar.

In 2009 they started an advanced workshop, the third of which will be held this summer. During this workshop they discuss ethics and understanding the questions you are trying to answer before starting analysis. Participants can bring an object that they have questions about and then they share the results with one another.

In the future they are looking for ways to broaden the community and making resources available to educators. Thanks to Nancy Odegaard and Dr. Hill for bringing this to our attention.

AIC’s 40th Annual Meeting – AIC Wiki Meeting, May 9

The AIC Wiki meeting provided active wiki Creators with the chance to connect faces with the names they’ve seen contributing over the past year, and everyone introduced themselves to the group. AIC’s e-Editor Rachael Perkins Arenstein noted that roughly half of those present were new to the wiki, and at the meeting to learn how to get involved.  She began by providing a brief background on the history of the wiki.

 

SG’s and the “Wiki Edit-a-thon”

There was an update on each specialty group’s use of the wiki.  The specialty groups shared their strategies for building participation in January’s “Wiki Edit-a-thon.”  The event was a great success, as Rachael described in the March 2012 issue of AIC News.  There were 137,000 hits to the wiki during the month, 59 new articles were added, and over 100 supplemental pages.  PMG had surveyed members and then set up two categories to populate during the event.  One day per week was scheduled as a “write-in” day, when members knew they could email each other to confer as they posted their content.  The Book Group in BPG set up a sample page for Creators to refer to, and it jump-started the creation of other pages.  EMG set up an outline and template, and then scheduled a single “write-in” day for everyone to join in.  Some groups, such as WAG, ASG, and the Paper Group in BPG, used the event as an impetus to identify people to spearhead their SG’s nascent wiki efforts.  OSG expanded their template, nearly doubled their number of Creators, and expanded content on a variety of topics, as well as adding new ones.  CIPP and TSG both realized that their Listservs had threads that would make great pages, so that will be a next step.

 

New Developments

The wiki software is outdated, and plans to update it are in development so that video can be embedded and the citation tool can be improved.  The wiki home page was reorganized, and there is significant interest in translating some of the wiki pages.  The first request came for a Russian translation of some of the content.  The translation will also be available on the AIC Wiki.  There’s interest in a Spanish translation of the Paper catalog.  A section on “The History of Conservation and Conservators” is in development and will include interviews from the FAIC Oral History Project.  Quality control and peer review were discussed, and what processes might be set in place across SG’s.  A working group is in formation to propose a series of headers (such as the “Draft” header currently in use) that would designate the stage of peer review for each page.  Contact Rachael (Rachael [at] amartconservation __ com) to join the group.

 

 

Getting Involved

An online tutorial is available for those interested in learning how to post content, and Rachael encouraged potential wiki Creators to get in touch with her to get added to the wiki email list.  The goal is to make the wiki a go-to resource for professional content for conservators, by conservators. One important note is that no one forfeits their rights to content they post on the wiki (the copyright agreement is what is used for post prints).  Members should feel that publishing on the wiki is a respected and valuable contribution to the field.

 

A key message of this session was this: your ongoing efforts to expand the wiki, whatever your time permits, are valued and appreciated!

 

To stay informed of updates on the wiki, visit the AIC wiki at www.conservation-wiki.com and scroll down to the Getting Started section.

 

AIC’s 40th Annual Meeting – “Exhibiting ourselves: presenting conservation” Session

Exhibits are one (powerful) tool for displaying the range of conservation activities and engaging with the public.  Exhibiting Ourselves: presenting conservation will explore issues related to the development and implementation of conservation in exhibitions as well as issues related to conservation outreach through exhibitions. This interactive session will feature audience participation in addition to presentations by the following speakers:

Tom Learner, Rachel Rivenc and Emma Richardson will present the various objects, hands-on didactics, video, online and published materials used to tell the technical story behind De Wain Valentine’s sculpture Gray Column in the exhibition From Start to Finish. This exhibition was organized by the Getty Conservation Institute to raise public awareness of the technical studies and conservation decisions that conservators routinely make with modern and contemporary art.

Christopher McAfee will share the outreach activities of the conservation team in the Church History Department of the Church of Jesus Christ of Latter-Day Saints, including signage, small exhibits highlighting preservation principles, public tours and videos.

Irene Peters will describe the benefits and challenges of working in a visible conservation lab and the solutions created at the Musical Instrument Museum to provide interpretation when the conservators are busy in other areas of the museum.

Cynthia Albertson and Anny Aviram will explore the efforts to include conservation-related content in the exhibition Diego Rivera: Murals for the Museum of Modern Art , as well as the various materials produced to accompany it, including audio and iPad application guides, website highlights, and materials for museum educators and family programs.

Sanchita Balachandran will examine the ways in which the conservation process has become an important part of the narrative of the new Johns Hopkins Archaeological Museum. This narrative includes creating and maintaining a traditional museum display, encouraging and enabling physical use of objects for study, and providing public access to the “behind the scenes” functions and discoveries typically made by conservators.

Come join us Friday May 11th in the San Miguel room at 9:30 am! Be prepared to cogitate, contibute and converse!