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Layered Adhesives: How to Reduce PVA Use by 80% on Paper-backed Bookcloth

Fig. 1. The adhesives used in this post. Left: Aytex P wheat starch paste. Middle: Jade 403N PVA. Right: Lascaux 498HV. A simpler variant just uses paste and PVA.

PVA (PVAc, Polyvinyl Acetate) is the adhesive most commonly used in book conservation to make cloth covered drop-spine boxes. Most of my clients prefer these to other types of boxes. For large and heavy books there are few other options.

While PVA is convenient and sometimes necessary for boxmaking, offgassing is a concern. The Library of Congress ( LC poster) found PVA is still offgassing after 6 years! Apart from potential damage to objects, it’s a plastic; most of us are trying to use as little as possible. The offgassing from PVA will not cause instant flaming death for books, it’s not ideal for longterm storage. Books with copper alloy bosses and clasps are especially vulnerable. Box structures like a cradle box, which have many layers of cloth–adhesive–board are most likely offgassing much more than a standard box. The Library of Congress study found that even a box made with 90% paste and 10% PVA still offgasses enough to fail the Oddy test. However, the concentration was much less than straight PVA. As I understand it, testing is ongoing, including other of adhesives like EVA.

There is not a single convenient and cost-effective substitute for PVA. What to do?

Fig. 2. Thick Aytex P wheat starch paste. For this purpose, straining is not necessary, the lumps get smoothed out on when pasting out. Or you can use your fingers. This is the way bookbinders traditionally used flour paste. Paper conservators, please don’t freak out.

Paste is difficult to work on paper backed bookcloth because of the slowness of drying, problems with adhering edges and turn-ins, bubbling during drying, unpredictable stretching, and weak cloth-to-cloth bonds. An example of cloth-to-cloth bonds are when the trays are attached to the case of a drop spine box, so two outsides of the cloth need to stick together. Lascaux 498HV (an acrylic) is expensive, dries quickly, but also forms a fairly weak exterior face cloth-to-cloth bond. PVA is, well, PVA. I’ve heard of several different approaches, sometimes involving methyl cellulose, but they all pre-mix the adhesives together. 

In my Layered Adhesive technique, different brushes are used for each layer directly on the cloth instead of mixing adhesives together before application. It sounds a little like amateur hour — I know — but allow me to explain. Each layer of adhesive performs a different function. I’ve been using this technique on all my boxes since 2023.

PVA use is reduced by about 80%. Paste provides most of the adhesion, small amounts of Lascaux add extra tack to prevent unadhered areas at turnins, corners and board edges. I’ve found PVA is still necessary when attaching the walls to the base of the trays, and when attaching the cloth covered trays to the case. I’ve only used this technique with Halflinnen cloth because I use it all the time. I imagine other paper backed cloths would be suitable, possibly with some modification.

A simpler variation just uses paste and PVA, instead of Lascaux in some areas. Even this cuts down on PVA consumption considerably.

THE TECHNIQUE 

Fig. 3. Coating the Halflinnen cloth with paste. Note the thick paste. A tiny jar of Lascaux 498HV uses a  separate container and brush.
Fig. 4. Adding a layer of  Lascaux on the edges of the board. The paste thins the Lascaux and adds more open drying time. The Lascaux greatly helps adhesion when turning in, preventing bubbles, etc… Stretching the cloth is still a problem, so it needs to be handled carefully.

OVERVIEW OF THE LAYERED ADHESIVE TECHNIQUE

  • Paste, Lascaux, and PVA all use separate brushes and are kept in separate containers.
  • Paper to board, and board to board adhesion uses thick (6g starch per 100ml water) wheat starch paste
  • Corners and board edges get a thin coat of Lascaux 498HV on top of the paste. This makes them easier to adhere than paste alone, and I find there are less problems with delamination or bubbling during drying. The Lascaux gets diluted when applied on top of the paste.
  • If making a 3 piece case, for example, use paste then put a little Lascaux 498HV on the head, tail and foreedge turn-in areas. Similarly, when casing-in, use paste then add a strip of Lascaux 498HV on the edges of the pastedown, where it overlaps the cloth turn-ins on the case.
  • When making drop-spine box trays, I find the strength of PVA necessary to attach the walls to the base.
  • When attaching the cloth-covered trays to the case, use paste, with a coat of PVA on top, at the edges, again at the exterior cloth-to-cloth attachments.

ADVANTAGES 

  • Paste is cheaper than PVA
  • Paste is better for the environment
  • Less PVA equals less offgassing
  • Paste stiffenens the cloth/board much more than PVA; I like the feel. It is also perfect for stiffening the wedges in a cradle box
  • The cloth is easier to smoosh together at joins and blends nicer
  • Paste flattens the fibers on the cloth so it feels smoother
  • Paste works wonderfully for adhering double walls together; a little slip then bam they stick
  • There is less waste than premixing paste with other adhesives
  • Paste has a long open working time
  • Ideal for cradle boxes with many cloth/adhesive layers

DISADVANTAGES

  • Paste has a long open working time
  • Uses more brushes, longer cleanup
  • There is a small learning curve, and it takes more time when working compared to PVA. Then again, if you are charging by the hour….
  • May not work for other bookcloths without modification
  • Cross contamination with paste of other adhesives, need to use up in a few days
  • This technique is likely more suited to making a one-off boxes, rather than production

SUPPLY SOURCES

Halflinnen paper backed book cloth. Colophon Book Arts Supply: https://www.colophonbookarts.com/paperboard/rohhalbleinen With commendable transparency the manufacturer provided information on the paper-to-cloth adhesive, which is a PVA (!) specifically Brand VA518 from Intercol (https://www.intercol.info/pva-glue/) Warning: This PVA can be reversed with an errant blob of paste left to soak in. Just saying. 

Jade 403N PVA. Conservation Resources. https://www.conservationresources.com/shop/jade-403n-adhesive/

Lascaux 498HV. New York Pigment Company. Recently formed by former employees of Kremer Pigments, which has closed. They are Kremer’s NY distributer. https://www.newyorkpigmentco.com/products/lascaux%C2%AE-acrylic-glue-498-hv

Aytex P Wheat Starch Paste. Polistini. https://polistini.com/products/wheat-starch-aytex-p

FURTHER RESEARCH

This isn’t perfect, but using less PVA is better than using more, right? I’m curious if others have found different workable techniques to cut down on PVA when used on bookcloth? Have you been able to eliminate it completely?

Fig. 5. An in-process cradle box, using the layered adhesive method. I just need to make the case and glue everything together. The flat spinepiece is an improvement from Annie Ujifusa, the wedge pull mounting (at the bottom) is Mitchel Gundrum’s idea, and I’ve started making these 5cm wide bookcloth pulls for ease of opening. Laminated with PVA of course!

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Thoughtful Deconstruction or Inappropriate Intervention?

“Thoughtful Deconstruction refers to the conscious removal of elements of a bound item to show physical aspects that were previously hidden. In this presentation I will make the case that book conservators should consider employing this approach to carefully selected bound objects so that they can then be used to foster teaching and scholarship.” —Todd Pattison, 2026 (1)

Todd, first of all I want to let you know how much I have personally benefited from your book history scholarship, and respect your conservation and bookbinding work. On top of all that you are a good egg! You have generously contributed to many organizations, and are justifiably prominent in the field. 

Given your contributions, influence, and stature — and at the risk of sounding like a scolding schoolmarm — this “thoughtful deconstruction” approach is all the more disturbing. I totally support the practice of conservators interpreting objects. I totally support preserving evidence of use and existing damage in books. I totally love seeing what the insides of books look like. I totally do not support conservators taking apart books to accomplish these goals! Obviously one can do whatever they want with their own books. But advocating this as an approach for book conservators, as you did in your March 17 presentation New England GBW Chapter and in your article 2025 Suave Mechanicals 9 article, makes me uncomfortable. (2)

Have you considered how thoughtful deconstruction relates to our American Institute of Conservation Code of Ethics? Several areas are problematic: it compromises physical integrity (Article II), it prioritizes scholarship/education over preservation (Article III), and it adversely affects function (Article VI). As a Professional Member in AIC, it is also my responsibility to promote the Code of Ethics (Article XIII).

Why physically deconstruct now? Why not wait for not-to-distant future imaging or other technologies to answer your questions? What information can be important enough to compromise the integrity of an (even damaged) book? Just because a book is slightly damaged or has little current market value, does it give us free rein to intervene further?

Altering a book during the course of a treatment —which will prolong the object’s life — is different than deconstructing a structure for scholarship or education. I would also like to point out that removing a pastedown entirely is extremely unusual in current rare book conservation practice, given how invasive it is. I don’t think I’ve done it since the 1990s. Typically only the spine edge is lifted an inch or so to insert a hinge.

I have a confession. In my article in SM9, I also show an image of a lifted pastedown and removed leather on one of my own books in 2014. In retrospect, it really wasn’t necessary, but it was interesting to see that the slips were not deplyed or frayed, and that the inner face of the board squares were colored with vermillion. I think I just wanted a cool looking photo. You might say I wasn’t thoughtful enough. And at least the way I did it, it is not close to 100% reversible; which may be the case for many other people’s deconstructions as well. At this point I would rather have it intact, but like many projects I doubt I will have time to get back to replacing it.

How do we ensure careful selection of items to be deconstructed? Towards the end of your article, you mention “taking apart a volume that is destined to be destroyed and turning it into one that can teach, illustrate, or illuminate … seems a worthy thing to consider ….”  I don’t think most of us would disagree; however, determining which books are essentially valueless becomes a slippery slope. Take your case study in SM9 of The Token and Atlantic Souvenir, 1834. Even if the title page and a couple of plates are missing, and you got the book for free, I consider this 192 year old book to be valuable cultural property: it is a rare embossed binding, signed by the binder, signed by the engraver, there is only one for sale on ABE for $8,500 (most of the value is from a John Quincy Adams signature), just 24 are listed in WorldCat, and it is important enough to be included in Wolf’s From Gothic Windows to Peacocks 1825 – 1855, 170.

I bet books that could be deconstructed without disagreement  – say a 20th c. publishers’ binding with thousands of virtually identical extant examples – will reveal little interesting information. Books that do contain interesting innards maybe shouldn’t have been deconstructed in the first place.

Todd, please, listen to me, I’m on my knees, I’m praying that you have the strength to conquer this demon of dissectomania. You can stop turning more books into #pattisoncondition, just lay down your bookbinder’s knife, and overturn your board soaking tray!

NOTES

1. Todd Pattison, from BOOK_ARTS-L Listserv, March 3, 2026 “**REGISTRATION OPEN** THOUGHTFUL DECONSTRUCTION: A Webinar with Todd Pattison”.

2. Todd Pattison “Thoughtful Deconstruction” in Suave Mechanicals Vol. 9, (Ann Arbor: The Legacy Press, 2025): 554-580.

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Thomas D. Conroy: A Tribute

Thomas D. Conroy – a friend and colleague – died on November 11, 2025. He was a bookbinder, woodworker, book historian, toolmaker; basically one of those people who knew something about everything.(1) Needless to say, his extensive knowledge often resulted in impromptu discursive lectures, accompanied not only with citations, but sometimes extended quotations from memory. 

Unusually, his wide ranging interests and experiences would often coalesce into useful information. He was my go to source for identifying all types of tools. Once I queried him on a “whatsit”; or unknown tool. It was an 18 inches inch with forged octagonal shaft, flattened and hooked at one end, a brass ferrule, and the other end extending through a beautifully turned wood handle.

Fig. 1. A Stuffer that Tom identified. A Starrett combination square is under it for scale.

Tom identified it as a stuffer of some sort, likely for horse collars. But not after a lengthy, though fascinating, unasked for treatise on the history of golf ball stuffing materials and tools. I’m sure Jack Nicholas couldn’t have given a more through explaination. That was Tom. 

His expansive and free-range mindset was cemented during his undergraduate years at St John’s University. Only half-jokingly, he once complained that St John’s had ruined his life; convincing him to accumulate ideas rather than money. Most of his adult life he lived simply but comfortably in Berkeley, CA. He obtained an  MLS from UC Berkeley. 

I suspect his scholarly rigor didn’t come from formal education; instead it sprouted from his stubborn autodidactism. He was an autodidact’s autodidact; fusing the history of books, woodworking, craft, general mechanics, and god knows what else into his unique take on things. 

His hard earned knowledge was freely shared. Sometimes his comments on blog posts exceeded the length of the original. I had to be careful when corresponding: a seemingly simple question could provoke a comprehensive answer a few hours later: a little slower than AI, but more accurate. I didn’t want to take advantage of his intellectual generosity by constantly pestering him.

Tom took a well-deserved pride in his writing. We primarily corresponded through writing, first in letters and later through email, and we usually discussed things, not personal history. I don’t think it was because we were reluctant to share; it’s just that we were both more interested in things outside of ourselves. Are writing chops genetic? He never mentioned to me his grandfather Jack Conroy, was a self described “proletariat worker advocate” and professional writer, with a Guggenheim fellowship and an armful of published books. Tom had a tremendous influence on my own work and as our relationship progressed over 30 years, I changed from a fanboy to a peer – at least in my own mind. 

Not content with theoretical knowledge, he was also a maker: working in metal, wood, paper, and leather. These converged in unexpected ways, guided by his Conrovian cosmology. (thank you John DeMerrit and Dominic O’Reily for coining this apt term!) One example was his clever set of nesting boxes explored the range of book housings for a single book. 

Fig. 2. A set of six nesting book boxes. From Right to Left: a full leather binding of Hamlet, a Zahensdorf style full leather fire resisting case, a French style chemise and leather edged slipcase, a full leather Solander Case, a cloth 4-flap folder, a faux book spine slipcase, and finally a cloth covered drop spine box. Photo: Emily Ramos

Another example is a group of bone folders he had shaped. They looked unfinished and crude to me, a puzzling departure from most of Tom’s work. He carefully explained that their form was a direct result of function, along with the philosophic underpinnings of this type of craft work. His self-imposed challenge was to alter the original shape of the bone as little as possible to achieve a functional tool, instead of compulsively polishing every surface.

He loved all types of tools. A set of band sticks in a virtually airtight leather case was another tool he made that I particularly admired. He explained that he had copied them from a set owned by another binder, reportedly in order not to steal them! True tool lust.  

Fig. 3. Screenshot of typescript and drawings of movement with Tom’s drawings. This was made before widespread use of personal computers in 1987. Source: https://cool.culturalheritage.org/coolaic/sg/bpg/annual/v06/bpga06-01.pdf

Tom was a prolific author, despite often complaining of writers block. One of his many contradictions. If you are not familiar with Tom’s work, here are two recommended articles.

First, his 1987 “The Movement of the Book Spine”. It is essential reading for any bookbinder or book conservator. In it, he organizes the craft knowledge of bookbinding spine engineering into a rational system. He acknowledges that this is theoretical: it is up to others to test his hypotheses. And you know what? Despite some minor disagreements I have, they hold up really well. 

In 2023 he wrote “Bookbinding in the time of Cholera”; the tale of a sewing key and a coincidence that lead to its identification. It’s a great read and demonstrates how disparate bits of knowledge can coalesce once critical mass is reached. 

Fig. 4. Thomas D Conroy in 2020.  He lovingly restored his French style percussion press. The tinfoil on the screw is not to prevent alien mind control; it simply keeps the grease off your forearms if you accidentally touch the screw.

The last time I visited him, we talked for a few hours about books and tools and associated tangents. He was apologetic for his occasional lapses in memory and general fatigue, yet was prolific to the end; publishing two articles in the 2025 Suave Mechanicals 9 and working on a final uncompleted article about bookbinder’s backing hammers.

Fig. 5. Different spring dividers. The Fay pattern on the far left was a gift from Tom. Later the patent was bought by Starrett, and their version is third from the left. Tom loved dividers, and when asked how many he needed, wrote, “six pairs isn’t too many. Sixty isn’t. Six hundred?… maybe, but I’ll let you know when I get there”.

Before I left his Berkeley house,  he gifted me a pair of original Fay dividers. As I stepped down the stairs of his weather eaten front porch he hoarsely shouted I could find more information in appendix three of Kenneth Cope’s American machinists tools. 

As typical with Tom, tracking these citations expanded into related patents, like the beautifully shaped Steven’s dividers. More interesting things to research. Endings are messy. Tom is gone. I’ll miss him.

Footnote

  1. Tom was also a lover of footnotes. Occasionally they even exceeded the length of his primary text. This mirrored his digressionary speaking style. This one’s for you Tom, apologies for the brevity!