Understanding Asian papers and their applications in paper conservation”: a workshop review by Laura Dellapiana

© Minah Song

Between July 11th – 14th, the British Library hosted the workshop “Understanding Asian Papers and their Applications in Paper Conservation”. The tutor of the workshop was the independent paper conservator Minah Song.

The course run in the British Library Centre for Conservation (BLCC), with intensive theoretical and practical sessions lasting three days. The aim of the course was to provide both emerging and established conservation professionals with the theoretical and practical foundation for understanding Asian papers and their applications in paper conservation, and it was specifically designed for paper conservators using Asian papers in their daily practice, or wishing to experiment innovative approaches for their conservation projects.
On the first day, the workshop started with a theoretical session about the history of papermaking in China, Korea and Japan (the three main countries that nowadays lead the paper market) by its first introduction (China, around II-I century BCE) to the present. Each country has a different soil, climate and craft tradition, that means the papers differ in qualities and properties even though the plants used for papermaking may be similar. Indeed, there are many different factors that may affect the quality of a sheet of handmade paper: the plant itself and the section used for papermaking, the techniques used to create the fibres (e.g. use of ash or caustic soda…), the bath (percentage of fibres/water, addition of a formation aid and its nature), the materials used for the mold, the technique used for the sheet formation (e.g. the Japanese Tamezuki/Nagashizuki methods, or the Korean Ssangbaltteugi/Webaltteugi), the drying method (hanging, on wooden boards, on metal boards…) and any surface treatment.
Our knowledgeable instructor Minah illustrated all the differences and focused on very important elements that can guide a Western conservator in choosing the most suitable paper for a conservation project. She also offered some tips in how to relate with paper vendors and about the elements to consider
if we look for a paper suitable for conservation. For example, we have to consider that the nature of the formation aid used during the papermaking process is not so important as the drying technique. In the afternoon of the first day, we started the first practical session: every one of us created a drying board with a honeycomb panel and machine made Japanese paper, coated with a solution of Lascaux 498 HV. This drying board follows the theoretical principles of a karibari board and may be useful because of its lightness and for large-dimension artefacts, through the combination of several boards.
On the second day, we learnt how to create a paper sheets with specific Asian fibres or a combination of different fibres. Our instructor pointed out that, in some cases, we conservators can make paper for our conservation projects using leftovers of Asian papers. We made small samples with a simple embroidery frame dipped into two special solutions: a bath with mulberry fibres (formation aid: polyacrylamide) and a bath with cotton/ linen fibres. I understood it requires some experience to control the thickness and uniformity of the final sheet, and it is important to know that, from the same bath, the first sheets will be thicker than the last sheets.
The mulberry paper sheets were mostly white with long fibres, while the cotton/linen paper sheets were creamy with short fibres. Those sheets may be beautiful for repairing losses, and can be treated in different ways (sizing, coating, toning…) if necessary.

Moreover, in the afternoon we discussed different toning methods and experimented in toning several Asian papers with acrylic dyes.
There are several possibilities for toning papers: fibre reactive dyes, Japanese traditional Yasha method (less frequent nowadays, also in Asian conservation studios), watercolours, natural pigments, and finally acrylic toning. This last method is frequently used because of the versatility and the stability of acrylic paints. The application methods we experimented with were brushing and spraying applications. On the third day of the course, we tried to tone different sheets of Asian papers (machine made Japanese papers

5-25 gsm, handmade mitsumata paper 30 gsm, handmade Korean paper #1101 12gsm) to repair losses on some newspapers and modern advertising papers that we had to treat. These samples were generously provided by our instructor. I personally found the airbrush application with acrylic paints very fast and versatile, and it was very interesting understanding how the different papers reacted while toning.
Regarding the toning and repairing phases of a conservation project, our instructor shared very useful tips to match the colour and the repair infill properly. During this section of the workshop, it was particularly interesting to see and discuss different methods from the different experiences of the ten course participants (from Great Britain, Italy, USA, France, Spain…).
On the third day, we used different Asian papers to prepare pre-coated sheets and discussed the preparation and uses of pre-coated materials in general and which Asian papers are suitable for specific purposes. During this discussion, I personally discovered an interesting new material: the Klucel M, different from the well-known Klucel G because it has higher viscosity and strength in lower concentration. Then, we tried a double-side lining with a machine-made, pre-toned Japanese paper 4gsm on a 20th century newspaper with wheat starch paste and a lining treatment with Korean paper #1201 13gsm using the drying board we prepared on the first day. In the afternoon, we finally tried the pre-coated tissues on different ancient western papers and had a final discussion on how to treat both Western and Eastern artworks with Asian papers.
We discussed the treatment of tracing papers, pith paper, Japanese scrolls and prints, archival materials of different periods with Asian papers. We finally shared some interesting thoughts about buying Asian papers from vendors available mostly in Europe: sometimes, it is possible to find adverts with information that are fascinating (e.g. “sun bleached paper”) but it is important to understand which are the useful selling points we must be aware of.
We had the extraordinary opportunity to visit the conservation studio of the British Library thanks to BL conservator Elizabeth Rose and have a “behind the scenes” view of the current digitisation project linked with the British Library Qatar Foundation Partnership Programme for the creation of the Qatar Digital Library, thanks to the BL conservator Flavio Marzo.

Overall, this was a very intensive and rewarding experience, and I particularly appreciated the chance to try out techniques and learn smart methods in a stimulating environment.
In addition, Minah provided us with a very detailed handout full of references, links and information to deepen our considerations about Asian papers.
This course offered to me the opportunity to refresh what I learnt in a few years of working experiences and research on Asian papers and with Asian artworks, and experiment, through the practical sessions, new methods for using these kinds of fibres.

I personally thank the BL staff and Minah Song for this wonderful experience and encourage other institutions to host the workshop, for example in Italy!