Our Assistant Conservation Officer, Eugenie Karen, explains some of the conservation issues relating to a beautiful Japanese print.
There are major changes afoot in the main exhibition space of the Treasures Gallery. Although we change the exhibits less frequently here, twice a year we look to offer a fresh view and new gems from the collection.
In the area designated for Prose and Drama we are putting a rarity on display. It is an 18th century print entitled ‘View of a Dramatic Performance at the Three Theatres, 1770-1790’ by Utagawa Toyoharu. This depicts the interior of a theatre. The artist is notable for the perspective techniques that he mastered and our print shows this to great advantage. Having had access to translations of Dutch and Chinese texts on geometrical perspective he began to apply the techniques to his own work.
While there are still a variety of colours to be seen the print is notable for the tones that are missing. Most notably the blue which would have been produced from the petals of the dayflower. Unfortunately the pigment that it produces is extremely ‘fugitive’ which means, as the word suggests, the colour runs away. In this case if there is exposure to the slightest moisture or light. The Japanese language hints that this unfortunate quality has always presented an issue. It was described as a dyestuff by the name tsukikusa, literally moon grass. The unstable blue colour seen in dyed clothes was cited in literature to describe ephemeral love.
Other colours have faded and although a specialist in Japanese prints judged that our copy had faded as much as it was going to, it is our responsibility to guard against the risk of further damage. To this end we will be keeping a very close eye on the object once it has gone on display. The case will be kept at a very low light level, around 50 lux, and we will monitor the humidity within the case.
We also photograph the print before and after display, comparing the colours and placing a blue wool scale which will help to monitor light exposure. This is a method of tracking the permanence of pigments. Identical dye samples are adhered to a card, one is hidden from UV light while the other one is exposed to the same light conditions as the object being monitored. The amount of fading can be assessed by comparison to the control.
The other pigments are also susceptible to damage and the slightest bit of moisture on the surface causes an obvious mark. This is so different to the usual etchings and engravings we work with that can happily be immersed in water and come out cleaner and healthier for it.
Mounting the print will be a challenge. Not only is the paper immensely fragile but it is stuck by some adhesive we are yet to identify to an acidic card backing from which it must be removed. Luckily the area of adhesion does not extend to the printed area so we should be able to do this safely while preserving the original mount for posterity.
This is undoubtedly one of the more challenging objects that I have been tasked with displaying but all the more interesting for it.