Methyl cellulose is a chemical compound derived from cellulose. When mixed with water, it can be used as a low-tack adhesive that is often added to PVA in bookbinding. The addition of methyl cellulose to PVA slows the drying time of PVA without compromising its strength.
Application of straight methyl cellulose to previously glued materials can also help break down and loosen old adhesive. It is used to clean old paper linings, adhesive, and super cloth from spines when preparing books for hollow tubes and rebacking.
Methyl cellulose is packaged as a granular white powder. Talas carries it in 8-ounce or 1-pound plastic bags that have eternal shelf life.
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| Your co-workers may raise their eyebrows when they see your baggie in the workroom. |
In a 2-cup container, add about 1/4 cup hot water to 2 1/2 tablespoons of methyl cellulose powder. Stir briskly to get all the lumps out. You'll have a white fluid that resembles partially-mixed rehydrated milk (white and grainy):
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| When the powder is well-dispersed, fill the container the rest of the way with cold water and stir. The result is a nearly-clear gel with some white grains still floating in it. |
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| Cover the container and let it sit overnight. The grains will absorb the water and soften into the mix. |
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| After 8 hours' rest, it will be a clear gel that is viscous enough to pour and spread with a brush. If it turns out thick and wiggly like Jell-O, mix in a few drops of cold water to thin it. |
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| Stir it in well when mixing with PVA. |
Opinions vary on what is the most effective ratio of PVA to methyl cellulose. A 50/50 blend is often recommended, but personally I think that proportion is too wet, and use more like a 70/30 (PVA/methyl cellulose) mix.
It is very helpful to use a blend of adhesives while gluing up large pieces, like book cover cloth or pastedowns. The mixture will be "wetter" than straight PVA, but remember that its drying time is longer and you can let the wet paper or cloth "relax" a bit before setting it in place. Remember to always insert wax paper between a freshly-glued pastedown and the text block!
Straight methyl cellulose can also be used to soften and remove old adhesive, making spine liners and inlays easier to clean without drenching them in water.
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| After a few minutes' absorption, use a dull paring knife to scrape away the old lining and glue. If one application of methyl cellulose doesn't remove all the old material, try another. |
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| This image shows the spine after two applications of methyl cellulose. Further applications will continue to loosen the old glue and eventually release the super and adhesive underneath (possibly animal glue, which may give this spine its orangey color), but this book is smooth and ready to have a new lining or hollow tube attached to it. |
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| Methyl cellulose applied to an old spine inlay to loosen paper and glue residue. Once dry, the saved spine piece can be mounted to a rebacked book. |
Fun facts about methyl cellulose! Abridged from Wikipedia:
Methyl cellulose is often added to shampoo, toothpaste, and liquid soaps to generate their characteristic thick consistency. This is also done for foods such as ice cream. Methyl cellulose is an important emulsifier, preventing the separation of two mixed liquids. *** When eaten, methyl cellulose is not absorbed by the intestines, but passes through the digestive tract undisturbed. It attracts water into the colon and is used to treat constipation and irritable bowel syndrome. A well-known trade name of methyl cellulose when used as a drug is Citrucel. *** Methyl cellulose is used as a variable viscosity personal lubricant; it is the main ingredient in K-Y Jelly. *** It can be employed as a low-tack glue which can be washed away with water. It may be used in the fixation of delicate pieces of art as well as in book conservation, to loosen and clean old glue from spines and book boards. Methyl cellulose is the main ingredient in many wallpaper pastes, is used as a binder in pastel crayons and some medications, and is used as sizing in the production of paper and textiles, as it protects fibers from absorbing water or oil.
Thank you! Fix-It Friday will return on April 13, 2012. Your inquiries, comments and suggestions are welcome!
Acknowledgements:
The Book Arts mailing list:
http://cool.conservation-us.org/byform/mailing-lists/bookarts/index.shtml
Chrisman, Michael. Bookbinders' Workshop Instructional DVD Series.
http://bookbindersworkshop.com/dvds.htm
Talas Bookbinding, Conservation, and Archival Supplies. http://talas-nyc.com
Wikipedia: http://en.wikipedia.org/wiki/Methyl_cellulose
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