What is urushi?

What is urushi ?
Urushi is the sap of the urushi (or lacquer) tree. Its scientific name is Toxicodendron vernicifluum (formerly rhus vernicifera). It is a member of the Anacardiaceae (sumac) family and is native to China, Korea, Japan, and the eastern Himalayas region. The sap contains the resin, urushiol, which when exposed to moisture and air, polymerizes and becomes a very hard, durable, plastic-like substance - lacquer! Urushi is, in fact, a natural plastic. Two similar trees with similar properties are found in South-East Asia.
There is evidence that stone-age peoples discovered the useful properties of the sap of the urushi tree. They first used its adhesive properties in the making of spears and arrows. In early Japan, people recognizing urushi's durability and shining beauty began using it to coat wood, pottery, baskets and bone objects to protect and strengthen them. From its first use in the making of bowls, plates, trays, sake cups, boxes, combs and other objects, the urushi developed along with culture.
In Japan urushi bowls and plates became a part of the harmony of traditional Japanese food. In the royal court culture classical styles were developed. Urushi techniques such as "makie" and "raden" elegantly use gold and silver to ennoble furniture, make-up accessories, toys, and writing implements.

Urushi also became an integral part of the harmony of Natsume (tea canisters), Kogou (incense burners) and other tools and utensils used in the tea ceremony. Outside the court, urushi was used in Buddhist temples and in the making of armor, helmets, swords, and other implements of war. In the Edo period, from about 1600 to 1867, people adorned themselves with beautiful urushi medicine cases, combs and hairpins. In the 17th Century, the Dutch East India Company introduced Japanese and Chinese lacquerware to Europe.
Today, while many craftspeople still make beautiful lacquerware, urushi has become an important material in the art scene in Japan and other parts of Asia. Contemporary artists are increasing working with urushi in their paintings, art objects and jewellery.
1) PROTECTIVE - Urushi is a liquid that can be applied to just about any surface, for example, wood, metal, cloth, ceramics, etc. When it solidifies, it becomes a very hard coating that waterproofs and protects the coated object from the effects of mold, mildew, and other forms of weathering. It also provides protection against caustic substances, such as acids. Only direct and prolonged exposure to sunlight will cause urushi to slowly deteriorate. Urushi's hardness and durability make it an excellent protective coating for any object required to be preserved and used continually over a long period of time.
2) ADHESIVE - The first use of urushi was as an adhesive. Stone age people first used it in the making of spears and arrows. They discovered that stone or metal arrowheads could be bound to wooden shafts using urushi. Today, its adhesive property is used to bind objects and to attach decorations using metal leaf, powder, shell, etc.
3) FORM AND SHAPE - By adding clay powder to thicken it, urushi can be shaped into decorative objects. Cloth is also be given form and shape by coating it with a rice glue-urushi mixture.
4) DECORATION - Urushi resin can be dyed black, red, brown, or yellow. Gold leaf, or powder is used to decorate objects. In addition, various types of shell inlay work is done to enhance the beauty of the objects. Especially in Japan, the decorative power of urushi has become an important aspect of its artistic culture.
In my works I use the traditional urushi techniques, "Kanshitsu", "Raden", "Rankaku", "Makie" and "Shitaji texture".
"Kanshitsu": First a form is made of clay or plaster. Then the form is covered in hemp cloth. Then it is stiffened by coating it with urushi adhesive, (urushi, clay powder, and rice glue), three to five times. This base is then covered by a urushi and clay powder mixture again three to five times. Next, it is polished until smooth using wet stone or sandpaper. Finally, at least two more coats of urushi are added. My works are large, but surprisingly light.
"Raden and Rankaku inlay" The piece is then decorated. Usually a shell inlay of abalone, mother of pear or sometimes egg shell is used. A layer of urushi binds the shell to the surface. The piece then receives more layers of urushi and is, finally, carefully polished.
"Makie" Makie is a traditional way of decorating an urushi surface. First, a drawing is etched on the polished flat surface. A coat of urushi is put on and then gold or silver powder is sprinkled before the urushi dries. After drying, another thin coating of urushi is put on the surface. Then after drying, it is polished. (Hira-Makie)
"Shitaji texture" This technique, an under coat texture method, is used before coating the urushi work. It is made of urushi and a clay powder mixture. It is thick, so it is possible to mold it like clay. After coating and before it dries, the surface is scratched with a comb, or a rolled string. This gives an interesting texture to the work. After this, it is coated with urushi, or first with metal leaf.