Urushi is a natural lacquer made from the sap of the lacquer tree (Japanese sumac tree). The sap contains the resin, urushiol, which when exposed to moisture and air, polymerizes and becomes a very hard, durable, plastic-like substance. That said, urushi is a natural plastic!
The urushi tree (Japanese sumac tree) is a member of the Anacardiaceae (sumac) family and is native to China, Korea, Japan, and the eastern Himalayas region.
In Japan, urushi and lacquerware have been used for various purposes, such as paint, adhesive and even protection since the Jomon period.
Since ancient times, urushi lacquer has been indispensable for agricultural tools and construction as the strongest adhesive in the natural world in addition to its use as paint in human life.
In the Asuka period (538-710), when the Buddhism has introduced from China, the demand for quality urushi lacquer has leaped for artistic Buddhist statues and religious sites.
During the Edo period (1603-1868), urushi lacquer art evolved uniquely in Japan. Works such as living tools and swords were sublimated from practical functionality such as durability and strength to Aesthetics.
Since urushi lacquer were produced in many areas in Japan at that time, each local clan encouraged the making of lacquerware. Traditional techniques of each region are still inherited.
Today, Northern 10 prefectures produce urushi lacquer in Japan and those domestic urushi lacquer accounts for only 3% of the total used, and majority goes to restoring the shrines and temples. The remaining 97% are imported from China.
Time to harvest urushi lacquer
An urushi tree takes 10 years to fully grow to collect the sap. Various care is required such as regular weeding, vine cutting, and protecting from animals. It is no exaggeration that most of the work of making urushi lacquerware is to properly grow lacquer trees.
Urushi lacquer collection takes place from June to October. The work is arranged to do little by little every 3 – 4 days because scratching on the surface to collect the sap puts a heavy burden on the tree. Just like blood for humans, taking out the sap for lacquer trees is life-threatening.
The only 200cc of urushi lacquer can be collected from a single tree. Depending on the time of collection, the quality such as transparency and viscosity will differ, and it will be appropriately used for undercoating, finishing etc.
Mid-June to mid-July | Hatsu-urushi (First urushi)
The advantage is urushi lacquer dries quickly.
Mid-July to Mid-September | Sakari-urushi (Blooming urushi)
The finest quality. Urushi lacquer has a beautiful glossy texture and transparency, and is used for finishing on the product.
Mid-September to October | Sue-urushi (Ending urushi)
Used for thickening the coating.
October-November | Ura-urushi (Backing urushi)
High viscosity and is mainly used as a coating base.
Features and Uses
Urushiol, which is the main component of the urushi sap, oxidizes and hardens, and exhibits excellent functions that are resistant to acids, alkalis, and alcohol.
Durability, water resistance, heat insulation and antiseptic properties are incredibly high, and synthetic paints superior to lacquer have not yet been developed!
Applying multiple layers of lacquer increases strength. Various decoration techniques have been developed over a long history, such as Makie, which draws patterns on the surface with gold and silver, and Raden, which expresses patterns with pieces of shells.
Also, Kintsugi, a gold mending, use urushi lacquer to bond broken pottery. With the advent of chemical adhesives in recent years, the aesthetics of urushi lacquer have come to be focused rather than the original function as an adhesive.
For daily use, bowls, trays, and jewelry boxes are popular, as urushi lacquerware has antibacterial and bactericidal effects. Urushi lacquer also prevents the growth of fungi and insects, so it is applied to buildings such as floors and ceilings.
Recently, a variety of urushi lacquer has developed with the mixture of urethane and cashew lacquer to make affordable urushi lacquerware. Our products also have both ‘new’ lacquer and old-fashioned genuine urushi lacquer, and each product has the description on product page.