Today the Preservation Lab says goodbye and thanks to our fearless leader (on the UC-side of the shop) Dan Gottlieb, Associate Dean of Collections and Scholarly Resources. Dan has been with University of Cincinnati Libraries for 48 years and has been our advocate since 2018. His contributions are many as a leader, but as a colleague we’ve always appreciated he thoughtfulness, willingness to lend a hand, and always showing up to our events. We wish you a wonderful retirement Dan!
The Lab recently received a collection of Exposition coins and an Exposition advert that were new acquisitions from UC Libraries’ Engineering Library.
While Ashleigh and Chris took on the housing portion of the project, I, of course, took on the documentation portion. This is one of the few times where scanning the object was actually the best route to take for documentation. I ended up scanning these after they had been safely and fully encapsulated in polyester film, and I was pretty pleased with how these scans turned out. Here are five of the exposition coins (rectos in left column and versos in right column):
These five coins were all encapsulated together with a Vivak backing layer and a 3 mil polyester film top layer, and then spot welded in place. I scanned them at 2400 dpi and then cropped each coin individually. And remarkably, this led to pretty successful scans of each coin while also keeping them safe and secure in the encapsulated package.
You can see how Chris and Ashleigh encapsulated and matted the coins on our Instagram –
If you’ve ever come across an old silver-based print, perhaps in a box in the attic, or an old family photo album, or even in a stored collection in a library archive, you’ve likely seen a pretty common phenomenon known as silver mirroring. Areas of the photograph will have taken on a shiny surface tarnish, a bit like a dull mirror.
Pictured: A “before treatment” image from a 2019 treatment to reduce silver mirroring. Note that the edges are more heavily mirrored than the center. Mirroring most often begins at the edges of a photograph.
There is a fun bit of chemistry involved in this, and we’re going to talk about that today. Note that this is just a quick overview of a LOT of information, so if you’re interested in a deeper dive, the information I’ll be discussing is drawn from the AIC Photographic Chemistry Series, particularly unit two, The Latent Image. The videos discussing the Gurney-Mott Mechanism, Photolytic Silver, and Silver Ion Traps can help provide an even greater understanding of these concepts.
Remember last month, when we went into valence bands and movement of electrons from the ground state to the excited state in order to become available for chemical reactions? Well, now we’re going to look at a bit of what happens once we have that excited electron, and how the reduction of silver ion becomes a silver metal. This process is the basis of photographic image formation, as well as the process that eventually leads to the aforementioned silver mirroring. This is known as the Gurney-Mott Theory.
Pictured: the Gurney-Mott Mechanism. Silver ion (Ag+) gains 1 electron and becomes stable silver metal (Ag0).
So, the light has struck our silver halide ion, and an excited electron has been generated. Now what? Well, first, we have to look at where that electron originates, the halide. Halide atoms, in a vacuum, have only 7 valence electrons. In that state, it’s uncharged, expressed as X0. It’s incredibly reactive this way. It really does not like to be uncharged! Halide atoms follow what is known as the Octet Rule. That is, they prefer to have 8 electrons in its valence band, for maximum stability. An uncharged halide will seek an extra electron to create that stability. When that happens, it becomes an X– ion and has a closed valence shell (it has maximum allowable electrons – it’s closed to additions.)
Pictured: The halide ion, in chemical terms. A stable ion (X–) is struck by light (hv), leading to the escape of an electron (e–). A recaptured electron will return the atom to the X– state.
Once that electron is stimulated enough to reach the conductance band and break free from the halide, it will roam and fall into a lower energy level, where it is drawn what is called a silver ion energy trap. This trap is a region of energy within the silver halide grain that pulls in and holds electrons. The electron is then sensed by a positive silver ion, which then comes seeking to bond with that free electron. The energy trap is the site of all of the reactions within our AgX crystal. These traps can be shallow or deep; deeper traps have higher energy and are more stable reaction sites.
In the early days of silver-based photography, these traps were formed entirely randomly. As you can imagine, it made the reactions a lot harder to control, and created a lot of guesswork and trial and error. Once the process was better understood, chemical sensitizers were introduced into the process to make things more uniform. The most common sensitizer is sulfide (yes, from sulfur; it’s noted as S2-). A sensitizer creates attractive, consistently deep traps for electrons to congregate. It’s a lot like digging a pit to trap a wild animal. Dig a deep pit, and once you lure the animal, it’s a lot harder for it to escape. Here, it’s electrons and the silver ions that will come looking for them in the world’s tiniest single’s bar.
Energy traps are essential to latent image formation. Without them, the meetings between free electrons and silver ions would be totally random, and the resulting photographic materials wouldn’t be very sensitive at all, which is no good. They also wouldn’t be particularly stable, as once you have silver ions and electrons in a trap, you want them to stay there as long as possible.
Now we have our energy trap, our electron, and our silver ion (Ag+). We’re all set for chemical magic. They meet, get friendly, and form silver metal (Ag0). This is the Gurney-Mott Mechanism in a nutshell.
If we can get four of these silver metal atoms to congregate in the trap, they will form a silver speck. Now we’re getting places! This is the key to photosensitivity. The more deep traps we can generate, the more sites of silver speck formation we have, the more sensitivity and better image formation we achieve.
Alas, time takes its toll on all things, including our Ag0 coupling. Silver, you see, isn’t the most stable of partners. It likes being Ag+, and it will work to get back to that state. Eventually, our Ag0 union will dissolve and the Ag+ ion will wander off. When this happens, the freed silver ions will migrate to the surface of a photograph and reduce to become silver sulfide. And that, friends, is how silver mirroring happens.
Hyacinth Tucker (UCL) — Bindery and Conservation Technician
About two years ago, I set upon a mission to gain expertise in the area of identification and treatment of photographic materials. Under the guidance of our conservator, Ashleigh, I developed an education plan that was split between the theory of learning the ins and outs of photograph identification, and the hands-on work of treating pieces that came into the Lab. Of course, these two things go hand in hand. If you can’t identify a piece, you can’t treat it correctly, right?
Fast forward to last year. With the start of the pandemic and the transition to working from home, my education plan changed radically. If I’m not in the Lab, I can’t spend much time on treatment, so I had to get a little creative and work on other ways to learn more.
I am about halfway through the series; a triumph for me, as I have never been one for the study of chemistry. I will say that while it is still very technical, I’ve had a lot of good pegs to hang the information on, owing both to my earlier studies in photograph conservation and my personal history with film photography. It’s been a tremendous thing, viewing things that I learned as a photography student from a different angle. So far, it’s been a great journey.
In this series, I will share with you some of the most fascinating things that I’ve learned so far. My aim will be to keep the technical as simple as possible, for those of you who are like me, still coming to terms with the deeper science. The small bites help it all make sense, I promise. Hopefully, you’ll find it all as interesting as I have.
Before we can understand anything else, we need to talk about halides. What are those and why are they used in photography? Good questions! Halide salts are derived from halogens, which occupy group 7A (column 17) of the Periodic Table of Elements (see below.) Halide salts are used in photographic emulsions that are spread over a substrate (such as paper or film) before the substrate is exposed to light. The silver halides react to the light to form an image when developed.
I should note here that silver gelatin prints, albumen, and collodion photographs all utilize silver halides in their chemical composition. However, silver gelatin is unique among the three in that it is the only one that uses a true emulsion; in albumen and collodion coatings, the halides rest on the surface.
Photograph – silver gelatin process
Photograph – albumin process
Photograph – collodion process
In forming the silver gelatin emulsion, halide salts are combined with silver nitrate and water to form silver halides, the compound at the core of silver gelatin photography. Silver nitrate is pretty much universally used regardless of halide salt, as it is water soluble (it dissolves) but not too much so. The freed silver will look for a bond partner, and the halides in halide salt fits the bill. As a result, silver nitrate, when combined with a halide salt in water, will result in silver halide and a left over salt.
This reaction, which seems like a lot, I know, is referred to for our purposes as “The Emulsification Equation.” To refresh our memories a bit, an emulsification is a liquid (here, gelatin) that contains fine particles of another liquid (the silver halide) without fully combining. Think mayonnaise, or butter. (This isn’t perfectly analogous, as silver halides are crystalline solids and not liquid fats, but the basic idea is the same.)
Chemically speaking, that reaction looks like this:
Equation for emulsification
As a quick reminder, Ag = silver, N = Nitrogen, O = Oxygen, K = Potassium, and Cl = Chlorine.
Now, if you’ll look at the image of the halogen column of the table below, you’ll see a number of options for salts to combine with silver nitrate. Older emulsions involved bromine or iodine; more modern emulsions tend toward chlorine. Crystals formed from silver chloride salts are much more uniform in structure, which makes its use outcomes much more predictable.
Salts that will combine with silver nitrate
I’m sure you’ve noticed that we’ve got a couple of halogens unaccounted for, namely fluorine and astatine. Neither of these are used for this kind of work, and for good reason. Fluorine, for its part, is very water soluble. Very water soluble. To put it in perspective, sodium chloride (regular table salt) is about 35% water soluble. I’m sure that in the course of cooking, we’ve all dissolved salt in water, and you can recall how relatively simple that is to do, though not without some small effort. Well, fluorine salts are about 172% water soluble! You could use it for your emulsion, but moments after developing an image in a water-based solution, you’d see it dissolve before your eyes.
I’ll note here very briefly that chlorine, bromine, and iodine are also more soluble than table salt, but not nearly as much as fluorine, making them perfect partners for our silver ions.
Meanwhile, astatine is…well, it’s radioactive. I think you can see the problem with this one.
And there you have it, a short and hopefully painless explanation of the humble halide in silver-based photography. In the coming months, we’ll be looking at other fascinating aspects of halides and our Emulsification Equation.
Hyacinth Tucker (UCL) —- Bindery and Conservation Technician
One of our most recent additions to our channel is the recording of our Virtual Lab Tour and Live Q&A, hosted by the Cincinnati & Hamilton County Public Library, which took place on Tuesday. If you weren’t able to join us live, please take a look; it was a very fun event and we had so many great questions from our live viewers.
Make sure to subscribe to our channel so that you can stay up to date on any new videos we add! And don’t forget to like videos, and we’d love to hear about what you’d like to see more of from us in the future.
Every year our staff, students and volunteers look forward to our Student & Volunteer Appreciation day, which we affectionately call “fun day”. It generally takes place in late November or early December, always before finals week. It is a time to show our appreciation for all the hard work our students, volunteers and staff do throughout the year, while having an opportunity to come together and learn some new bookbinding or book arts technique. In the past, we’ve done paper marbling, made handmade paper, created German long stitch binds, and more.
I have been coordinating our student & volunteer appreciation days for almost as long as I’ve been in the Lab, so for at least 12 years now. I love it because I am the type of person who enjoys planning these types of things, but also I love watching a student, volunteer or staff member just get really excited about something new. You never know if it’s going to be that quiet new volunteer who just can’t get enough of paper marbling, or that student who doesn’t have any art background but just does the most amazing pulp paintings ever! So after all these years, the thought of 2020/the pandemic ruining everything and not having any sort of student/volunteer appreciation day was just unacceptable!
I immediately thought, “What types of activities could we do virtually that would be no cost to the lab and would give everyone a couple hours to come together and decompress?” After a little brainstorming with Holly, we came up with a Button Hole Stitch binding (which I had recently learned) and a simple dissolving view. With the help of my wonderful student staff member and cohort buddy, Lexie, I prepped kits for our virtual event, as well as prepared a step by step video on creating a button hole stitch binding.
Here are some of the beautiful creations that came out of our little virtual fun day:
Last month, I showed you how to make a corrugated clamshell. At that time, I mentioned some alternative strategies for special situations, such as considerations of working space, collection size, etc. Pre-made boxes may be the way to go here. They’re generally non-adhesive, and excellent if you have a large collection that needs help, but can’t be worked on right away, for pieces going to off-site storage, or if you’re in a situation where box building space is at a premium, such as many of our work from home setups (I’m currently working at my kitchen table, which is definitely a squeeze sometimes!)
There are multiple ways to obtain pre-made enclosures:
Many commercial binderies offer custom economy boxing. Our Lab uses HF Group (http://www.hfgroup.com/) when needed. Their work is excellent, and their enclosures can be created from sent measurements. This is wonderful for housing items in our collection that require storage, but we feel are too fragile to be shipped.
A pre-made enclosure can also be a great option for very small items, to keep them from becoming lost on the shelf.
Under normal circumstances, a box created in the Lab for a small piece would be lined with foam to keep it from moving around in the larger cavity, but when the pandemic hit, we thought it might be a good idea to find ways to do this that didn’t require foam, which might be expensive or difficult to source or store.
Enter the Kyle Insert. Developed by Kyle Olmon, it is an answer to the ongoing question of new ways to store smaller items that will keep them safe and prevent them from getting lost. It works well for things like artist books, which are often incredibly small. It’s also a time saver in lieu of foams. I don’t know about you, but cutting foam is not my favorite thing. An alternative is always welcome when it is appropriate, and we (and the books!) can always benefit from having multiple ways to solve problems.
Written instructions from Kyle Olmon are available on-line at https://kyleolmon.files.wordpress.com/2016/05/kyle_insert_v2_instructions.pdf . I found that the insert made more sense to me when I had a visual representation. It’s a surprisingly simple structure but may not seem that way on paper. In light of that, I did something a little different and put together a video of my assembly efforts, interspersed with instructions and diagrams from Kyle Olmon throughout. Hopefully the video combined with Mr. Olmon’s excellent instructions will help you get started with this form!
Admittedly the title of this blog is a bit dry, but whenever I see the phrase stationery binding my eyes dart and the corners of my mouth start to move upward. Since trying my hand at an accounting book at Paper and Book Intensive 2017 in Chela Metzger’s workshop Early Modern Record-Keeping Book Structures, I have enjoyed learning more about their variations, creating historical models, and using the form as an inspiration for artist’s books.
After digging into Katherine Beaty’s essay Tackets, Buckles, and Overbands: Italian Stationery Bindings of the HBS Medici Family Collectionthe in the latest volume of Suave Mechanicals (http://www.thelegacypress.com/suave-mechanicals-vol-6.html), I decided to attempt a model of the second largest laminated archival bind. Beaty’s essay provides excellent descriptions of the various accounting books within the Medici collection, helping guide me in the construction of the model and filling in large gaps in my knowledge.
Katherine Beaty’s essay is not a “how to” manual, so all the errors and false assumptions that present themselves in the final model are mine alone. Making this at home with materials I had on-hand provided some challenges, so there are some missteps in terms of historical accuracy. But, in the end I’ll give the final product solid B for effort! And I had a great time making it.
Laminated leather archival binding with buckle fastening, size 34 x 27 cm.
Tuxedo boxes are fantastic, accessible enclosures. Sadly, they do have their limitations, as anything does. If you’re working with a piece that is a larger or heavier (or both!), a piece that is a bit more delicate and in need of more protection, or a piece that isn’t all in one piece, you may want to look at a corrugated clamshell.
The corrugated clamshell is a slightly more complex, yet infinitely versatile addition to a good basic preservation enclosure arsenal. Developed by Andrea Krupp in 1988, it’s great for pieces that are awaiting treatment but need stabilization in the meantime. It also works beautifully for boxing sets of items that don’t quite merit the time commitment that a cloth-covered clamshell might. I have also found a corrugated clamshell to be perfect for things like experimental music scores (which may include cards, CDs, or any number of other unexpected items) that need to be shelf-ready in a hurry.
So let’s make one. The material list for this is actually surprisingly small:
A cutting implement, such as a scalpel or X-acto or Olfa knife
At least one ruler. I generally use two – a meter rule for laying down lines, and a 12-inch rule for most cuts.
A bone folder. This should have at least one end that is fully rounded. You don’t want to push through your board!
PVA; archival quality, of course. While there are a few ways to make a non-adhesive box that I won’t get into with this entry, the method we use here in the Lab does require it.
A way to secure the adhered portions of the box. In the Lab, this would be done with large bulldog or binders clips with board scraps to prevent marring, but if you’re at home without something like those, some strategically-placed weights will do nicely.
And of course, your corrugated board. Again, archival quality. For most projects, we use B flute (3mm thickness), but we do use E flute (1.6mm thickness) as well. E flute is used for my example photographs, throughout the entry.
In the Lab, planning for our corrugated boxes begins with an Excel spreadsheet. Brought to us by Ashleigh via UCLA, this greatly shortens our box making time by automating the measurements needed for each project. With just the height, width, and thickness of your piece, the sheet maps out every measurement you need for a snug, custom enclosure. As you can imagine, in a production lab like ours, this is a huge boon. I highly recommend it, and I would be happy to send it to you! (Feel free to email me any time at hyacinth.tucker@uc.edu or check out this link to past OPC workshop handouts!)
E flute spreadsheet, prepped and ready!
Corrugated board, ready for cutting and scoring.
Once we have our measurements secured, it’s time to cut our board down to size and lay down our guide-lines. Two things to remember: 1) be sure to make all your markings on the side of the board with visible corrugated lines, this way the guide-lines and the less aesthetically pleasing side of the box are on the inside of the enclosure (with the exception of fragile items that might rub against the corrugation such as red rotted leather); and 2) do your best to orient the grain in the proper direction. When the box is finished, the visible corrugated lines should run in the same direction as the spine of the book. The overall board sizing can be done with your larger ruler, rather than a board shear or oversized paper cutter, if you’re very careful. That same ruler can then be used to measure out the cutting and scoring lines.
Work in progress, a closeup of a flap cut.
Next, let’s make our box cuts. If you have one, the smaller ruler is great here. Again, the spreadsheet makes this part simple. Cut on the solid lines, score and fold on the dashed lines. One thing that the sheet doesn’t mention is that the inner corners of each box wall need to be cut. Not much; you don’t want to expose your materials to the elements. Just a little corner to keep them from catching on each other when you close your completed box.
Almost done!
Now that all of the cuts are done, we move on to the scoring and creasing. In the Lab, all of the creasing across the width of the box is done with a large crimper, and the lengthwise work is done by hand. Fortunately, if you don’t have access to a crimper, it’s pretty easy to score with one of your rulers and the rounded bone folder. Just take your time, and don’t press too hard; you don’t want to break through the board.
In the absence of bulldog clips, properly placed weights can help hold everything together while the adhesive dries.
Next, let’s pull it all together. First, fold up the sides of your box, to define your inner trays. If you are using 3mm board, this is a great time to use your bone folder to flatten the flaps, in order to prevent bulk when pasted down. Next, tuck the flaps into the fold over portions at each end. This is where the PVA comes in. Put it on the flaps and the interior of the fold-overs. Be generous, but not too generous; we don’t want it to gush out when we make the folds. Secure the fold-overs with the clips/weights, and leave it all to dry. I aim for overnight, if I can, so that the PVA can off-gas a bit before I put the piece inside. If you can leave it for longer, that’s even better.
And there you have it, a lovely custom corrugated clamshell that’s perfect for your needs. In my next post we’ll look at some non-adhesive solutions, and a great way to customize them.
Until next time!
Hyacinth Tucker (UCL) — Bindery and Conservation Technician
When in the course of an item’s history it becomes clear that the book or artifact could use extra attention, or just another element of design to aid in its care and preservation, we create enclosures.
Enclosures create a microclimate that provides a darker more consistent environment for works to be stored in. There are many types of enclosures used for many different reasons, ranging from an impermanent simple paper wrap to more long-term solutions such as cloth covered clamshells.
We use enclosures to provide a range of protection for their contents.
A microclimate providing enhanced consistency concerning heat and humidity fluctuations.
A barrier against damaging UV rays.
Dust and pest control.
A strong support for contents.
Because there is so much documentation done on customized high-end enclosures that require greater skill and experience, such as cloth covered clamshells, I will discuss easy to make, low cost enclosures. To be honest, saving time and money is at the forefront of any business. Enter the elegant tux box.
A tux box serves admirably the need for a cheap, easy first line of defense. We usually create tux boxes using 20-point Bristol board with measurements custom to the book. The tux box provides an adequate barrier against dust and light. Another virtue of the tux box is thatold books that have suffered degradation and have become brittle are provided a more stable structure for storage and handling. It should be mentioned though that because of the nature of the design, temperature, humidity and some dust and light may enter inside the tux box through the exposed corners, possibly allowing these damaging elements inside.
So, let’s make one.
First make 3 jigs. The jigs will provide a guide to add extra board thicknesses to our book box dimensions to account for overlapping our boards during folding. We use 20-point Bristol board. Our jigs are three thicknesses – 1 thickness, 2 thicknesses and 3 thicknesses. We’ll label them 1,2 and 3.
Let’s also make a handy-dandy information guide that will record all our objects measurements and identifying info on a scrap of bristol board. Record the books thickness (TH), width (W), height (H), call number and title of our book. Use tic marks to record measurements as seen below. This will be useful for quick reference as we create our tux box.
There is a grain direction in Bristol board, (the grain direction is which way the fibers are aligned) for this purpose we will cut 1 length of the Bristol board with the grain running the (H) of our book and 1 length the (W) of our book plus 1 board thickness (W+1BT).
Use our information guide and jigs to measure, score and fold the horizontal or inner height-based board as follows: (W-1BT), (TH), (W), (TH) then (W-1BT).
For the outer vertical width-based board we also score and fold starting with an x lightly placed in the corner to identify the outermost flap. With our information guide and jigs and starting from the side with our x we measure, (H), (TH+3BT), (H+1BT), (TH+2BT), (H).
Wrap the horizontal piece around the book and then fit it into the vertical part. You can either use double sided tape or PVA to adhere these two together.
Here is the tux box in its open position. Note where the two boards are joined – only the panel where the back cover will sit.
Next, the tricky part. Creating the flap to secure its closed position. Measure, mark and cut the tongue on the outermost flap, let’s use a visual for this part.
Lastly, cut a slot for the tongue to fit into which secures the tux box closed. Close the tux box as if it is finished with tongue out. With a pencil draw a light “v” in the corner where the tab lays closed. Open the tab and place 2 small holes with a Japanese hole punch or an awl. Cut 2 lines connecting the holes forming a slot. Fit tab into the slot to close. Feel free to round the corners of the tab and all flaps using a corner rounder.
Tux box in the open position.
Tux box in the closed position.
You can also customize tux boxes to accommodate a varity of book sizes. No one wants to add an enclosure to their collection that is the size of a miniature book, it would be so tiny it would get lost. We can adapt the enclosure by adding spacers to bring the overall size of the tux box to at least 5”x7”.
Here is a link to an adaptation made to a clam shell that could also be used in a tux box as well.
So, the tux box is an easy-peasy solution for an extra layer of strength and protection for its contents. Unlike the Hostess Twinkie, the tux box is not expected to endure the apocalypse. I feel given the cost of materials and time spent to make one, it’s a fine, adaptable addition our enclosure family.
Chris Voynovich (CHPL) — Senior Conservation Technician
