The process works as follows: after removing the sap from the tree, it is aged for three to five years before it can be processed into a number of lacquer types with different properties. The processed lacquer is almost transparent and gains its colours from pigments that are added to it. The best environment for hardening lacquer resin is highly humid and hot. Each layer has to be completely dry to then be polished before the process can be repeated with the next layer. Once the lacquer is given its final transparent coating, it is waterproof, resistant to salt, alcohol and even alkali and acid. It also insulates heat and electricity.
Lacquer has an incredibly long tradition in Japan. Excavated objects show evidence of its usage as far back as the Jomon period (approximately 2500-1000 BC.). During the Edo period, when the arts especially prospered, lacquer ware was very much in demand: it was first used to decorate the residences of daimyo, feudal lords and shoguns, as well as middle class dwellings later on.
Japanese lacquer (urushi) comes from the sap of Rhus verniciflua tree. It was initially used to preserve objects and later on utilised for decoration. A very versatile substance, lacquer can be applied on wood, leather, paper and basketry. It can be spotted on a variety of antiques, such as samurai armour and calligraphy boxes (suzuribako).
Urushi contains urushiol, a poisonous substance to touch until it is dry, which makes the lacquer ware occupation hazardous and something that can only be practiced by skilled artisans. The complexity of lacquer production calls for a team of specialists and cannot be taken on by a single individual.
In the 18th century, experiments led to the development of coloured lacquers, which were further diversified through Chinese methods cultivated and perfected in Japan. The artistic effects of plain red and black lacquers were supplemented with inlays of ivory, seashells and similar materials, along with other techniques. These include:
roiro: black lacquer, polished to obtain a deep gloss
aogai: “blue and green shell”, pieces of shell inlayed into an usually black background
makie: “sprinkled illustrations”, designs are created with gold powder, sprinkled out onto wet lacquer, sinking to the bottom of the wet coating. As the urushi dries, it is polished down slightly to bring out the pattern. The process is repeated a few times
fundame: similar to makie and nashiji. In this case, the powder is too fine to be polished; the effect is a smooth matt surface
nashiji: a “speckled pear skin” effect using metallic dust. Process is similar to hiramaki
hiramakie: “flat sprinkled picture” made by using metal or coloured powder
raden: inlay of large thick pieces of opalescent pearl-shell
heidatsu: silver and gold sheet inlay
takamakie: building up layers of lacquer in high relief by using clay or charcoal