Repairing of tears in antique paper artworks.
Repairing even the smallest pieces and chips of paper is very important in the effort to conserve a piece of art. The tiny missing chips or tears can cause even bigger problems in the future. Tearing starts to occur when the fibers of the paper are bent, folded or damaged in any other way. Mold activity will decrease the structural binding of the paper fibers. Acidic mattes, tapes, cardboard backings will also cause problems in the paper. Because of all these influences, the paper will eventually become brittle. When the piece is handled, tearing can occur, especially near to the edges of the paper. So mend this if you can. When done right, the mending of the tear will be almost invisible to the untrained eye.
So we strife for a nice clean sharp cut edge to prevent further tearing of the artwork at the fragile parts of the work on paper.
Obviously big tears need to be repaired, the work looks much better when the tear is mended and also, it prevents an even wider tear in the future. For the mending process I use a wheat starch based, home made glue, called Shinnori, which is a fresh wheat starch glue. The glue is free from harmful chemicals that can damage the artwork in the future and can be very easily removed if necessary. Next to the glue I use Kozo Mulberry paper of different thickness to mend the tear with. First step in the gluing process is preparing the glue, (Shinnori) itself. There are many theories on how to prepare the Japanese wheat starch glue. Some prefer cooking the mixture for up to an hour, some take twenty minutes of actual cooking the glue paste. I tend to keep preparation time somewhere in the middle. Twenty to forty five minutes usually gets a good consistency. I also store my lump of glue in the fridge in a clean container with a lid on it. You don’t want any microorganisms feasting on your wheat starch paste. After a week you’d better throw it away, just to be sure, not to introduce invisible mold spores onto the piece of art. A very good recipe can be found here. After I have prepared the lumpy glue, I store it in the fridge. And when i’m ready to use it, I’ll strain it through a very fine sieve and mix it with distilled water until a good consistency is obtained.
The Kozo paper comes in many thicknesses. Pick the thickness that is the closest to the paper you are about to mend. Don’t cut the Kozo paper in strips, but tear the strips of Kozo in a shape that matches the tear you are working on as close as possible.
As mentioned before, the glue is used for mending tears. Also, some artwork that is in very poor overall condition with a lacking structural integrity, can be glued, or mounted if you will, on a piece of Kozo paper ,again with the help from the Shinnori glue. You will have to make sure that it is as finely structured as possible. Just mix the Shinnori glue paste with demineralized water, and with a sieve make this mixture as fine as possible.