Tuesday, January 24, 2012

Guest Post: A Final Internship Experiment

This is the final guest post from our intern and North Bennet Street School graduate, Arini Esarey. Her last project in Preservation Services was an experiment with a new technique for creating a conservation-friendly leather substitute to be used in bookbinding and repair. Our thanks to Arini for her excellent work and positive energy in the lab over the last few months, and best wishes to her as she leaves us for new adventures in the book arts. To contact Arini or learn more about her work, please visit her website.

The following experiment is based on the technique described by Grace Owen and Sarah Reidell in their presentation at the 2010 American Institute for Conservation of Historic and Artistic Works Annual Meeting in Milwaukee, Synthetic Leather for Book Repair: Experimenting with Cast Composites. In this activity I am not attempting to match existing leather for a specific book repair, but am merely curious to see how the technique works.


  • Japanese tissue (Hiromi Paper; HP-10B Kaji Natural, 24.5 x 39 inches, 26 g/m2, kozo fibers)
  • Acrylic Paint (Golden Fluid Acrylics in Burnt Sienna)
  • Silicone mold made from an existing piece of leather or cloth. (The one I used was already made by others in the lab. Owen and Reidell suggest a Room Temperature Vulcanizing (RTV) silicone mold kit available at art stores.)

Round 1
Undiluted acrylic paint was brushed lightly onto the silicone mold. Care was taken to apply as light a coat as possible while still achieving an even, opaque coat. Even so, not all brush strokes were eliminated, as you can see in the samples. Then Japanese tissue was laid over the mold and tamped down with a stiff brush. The tissue was left on until dry and then peeled away.

Sample 1: dry tissue
Sample 2: tissue dampened with water before application to mold
Sample 3: tissue dampened with Methyl Cellulose before application to mold

Round 2
In this trial, the acrylic paint was mixed with Methyl Cellulose before application (in a roughly 60/40 water to MC ratio).

Sample 4: dry tissue
Sample 5: dampened with water before application to mold
Sample 6: dampened with Methyl Cellulose before application to mold

Of the six samples, numbers two and three show the most promise for use in leather or cloth repair. Sample two has the most even application of color and texture with no signs of brush strokes. Sample three could be useful if the tissue is toned beforehand with a wash of light acrylic paint to add depth and richness of color to the final result.

Round 3
In this round, undiluted acrylic paint was dabbed onto the silicone mold using a piece of cheesecloth. The tissue was left to dry, then given a layer of Methyl Cellulose before putting the tissue onto the mold. After removing the tissue from the mold, half of the surface was given a bit of SC6000 and Klucel-g to mimic the treatment one might give in a repair treatment. Then, on the lower portion of the sample I under-painted a layer of black and burnt sienna to see how that would alter the appearance of the tissue.

Sample 7: tissue brushed with thin wash of burnt sienna, raw sienna, and water

Detail view of the sample with toned tissue, under-painting, and SC-6000/Klucel-G mix

Round 4
This time, I combined the elements I liked best to use for covering a scrap piece of board.

  1. Toned tissue with thin wash of burnt and raw sienna, let dry
  2. Dampened with methyl cellulose
  3. Applied undiluted acrylic paint into silicone mold using cheesecloth
  4. Under-painted the tissue with black and burnt sienna
  5. When dried, applied to piece of board with PVA
  6. Then, SC-6000 and Klucel-G applied to tissue

In the end, I’m pleased with the results of Round 4.

When attempting to match tissue to an existing piece of leather or cloth, the under-painting step may not be necessary, depending on what colors you use for the color wash and mold. In this demo, I liked the richness that layer of paint gave, even if it did add an extra step to the process.

This cast composite technique was introduced to me by Helen Bailey at the Dartmouth conservation lab in Preservation Services and Henry Hebert, currently a second year student at North Bennet Street School. Thanks to Stephanie Wolff for her guidance and support in the lab while working with this technique.

Thanks, Dartmouth Preservation Services for the chance to learn, experiment, and participate in the book conservation field. The internship was wonderful!

Written by Arini Esarey


  1. interesting! you missed some explanation steps in round 3 & 4 though.

    what was dried in round three (what did you do to it to necessitate drying?)

    when did you apply the paper to the mold in round 4?

  2. Hi, thanks for your questions. In round 3 the tissue was given an initial wash of acrylic paint. That was let to dry before applying methyl cellulose and taking the mold impression. In round 4, the paper was applied to the mold between steps 3 and 4 (after the paint was applied to the mold and before the under-painting).

  3. This is really interesting. I enjoyed going through every single bit of it.