Japanese paper is a good substitute for leather in many book repairs. Its easier to work with than leather, less expensive and can be waxed to give it a leather-like appearance. Obviously, it needs to be used selectively since leather rebacks are often the best solution for more valuable bindings, as well as being more fun to work with.

Coloured Japanese paper is sold by various suppliers under the name of Moriki, but with limited colours and weights. Rarely do the Moriki colours match the colour of the binding being repaired and often the weight is too heavy or light for the repair. To solve these problems, the most common solution is to colour undyed paper with acrylics mixed in water. When covering a larger area it can be a bit cumbersome, if not difficult, to adequately and evenly cover the paper needed.

To solve this problem we have been experimenting with using Hewit leather dyes to colour Japanese paper. This gives us an unlimited rage of available colours and weights. We have been using an airbrush to get an even application of colour. Using the airbrush and the dyes gives us the ability to dye pieces of Japanese paper as large as the backing board we tape the papers to before colouring. Often we will dye a piece twice as large as we need in order to put it in our "Moriki drawer" for future use. If we miss a colour we will also spray a piece anyway and store it away for future use, and surprisingly they are often soon needed and used. We have used a wide array of paper from Hiromi Paper.

Our method has been to store the Hewit dyes in small plastic bottles at a dilution of 9 teaspoons (45 ml according to my metric converter) into 90ml of distilled water. We wanted to make as concentrated solution as possible without creating a super saturated solution. It seems easier to match colours using the dyes in a liquid form, and using pipettes makes it possible to be pretty exacting in measurements. Some of the dyes dilute more easily in the bottles than others, some stay suspended in the water while others separate. I understand that is due to the amount of starch added to the dyes and has no relationship to their effectiveness. We give them all a good shake before use.

We also mix the colours using plastic transfer pipettes (one for each colour) in distilled water using a disposable food container. This allows us to save the colour for touch-ups until the book is returned to the client. The colours are tested using a cotton swab on the paper we are using and left to dry. Using heat to dry the paper does not seem to affect the colour, but we prefer to air dry the test as we always air dry the final paper.

This process should not work! Hewit dyes are formulated for use with their leathers and need more acidity than is in the distilled water (using pH testing strips we find our water to be around 5). However our experiments and tests have left us optimistic about this process. The papers need to be fixed using the Hewit fixative. After this step the dyes are very stable. We have tested them by dropping pieces of dyed Japanese paper into water and leaving them for several minutes and very, very little colour has left the paper.

Considering that after these papers are applied to bindings they are covered with Klucel and often a wax coating I have little concern for the colour coming off the paper. We have also tested them for light-fastness and they hold up very well.

We will continue to investigate and test the dyes, papers and the process for future publication but for now this is a very promising and easy method to create an unlimited range of repair papers.

Ed - Mark and the Panther Peak Bindery have posted a very helpful instructional video on this topic on You Tube at: www.youtube.com

Mark Andersson is a book conservator and binder working in Tucson, Arizona at the Panther Peak Bindery - www.pantherpeakbindery.com. Prior to moving to Arizona Mark was Department Head of the Bookbinding department at North Bennet Street School for nine years. He also worked at the University of Washington, spent a glorious year in the conservation lab at Uppsala University in Sweden and is a graduate of the NBSS program. Currently, Mark is the President of the Guild of Book Workers.

Bailey Kinsky is from Lakeville, Minnesota, and received her Bachelor's degree in Art History from the University of Minnesota, Morris in 2009. She plans to pursue a graduate program in Art Conservation in the near future. Bailey is currently participating in studio art courses and undertaking an interdisciplinary research project involving the chemistry behind synthetic oil paints. In addition to an internship at Panther Peak Bindery with Mark, she also is a conservation intern at the Western Archaeological and Conservation Center in Tucson, where she has been gaining experience in objects conservation. Currently, she resides in Tucson with her husband, Owen, and their two cats, Loki and Wicket.