| Toxicodendron vernicifluum | |
|---|---|
 | |
Scientific classification | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Clade: | Rosids |
| Order: | Sapindales |
| Family: | Anacardiaceae |
| Genus: | Toxicodendron |
| Species: | T. vernicifluum |
| Binomial name | |
| Toxicodendron vernicifluum (Stokes) F. A. Barkley | |
Toxicodendron vernicifluum (formerlyRhus verniciflua[1]), also known by the common nameChinese lacquer tree,[1][2][3] is anAsian tree species of genusToxicodendron native toChina and theIndian subcontinent, and cultivated in regions of China,Japan andKorea.[4] Other common names include poison sumac,Japanese lacquer tree,[5]Japanese sumac,[4] andvarnish tree.[5] The trees are cultivated and tapped for their toxic sap, which is used as a highly durablelacquer to make Chinese, Japanese, and Koreanlacquerware.
The trees grow up to 20 metres tall with large leaves, each containing from 7 to 19 leaflets (most often 11–13). The sap contains the allergenic compoundurushiol, which gets its name from this species' Japanese nameurushi (urushi (漆)); "urushi" is also used in English as a collective term for all kinds of Asianlacquerware made from the sap of this and related Asian tree species, as opposed to European "lacquer" orJapanning made from other materials. Urushiol is also theoil found inpoison ivy andpoison oak, to which the tree is related, that causes arash.
Sap, containingurushiol (an allergenic irritant), is tapped from the trunk of the Chinese lacquer tree to produce lacquer. This is done by cutting 5 to 10 horizontal lines on the trunk of a 10-year-old tree, and then collecting the greyish yellow sap that exudes. The sap is then filtered, heat-treated, or coloured before applying onto a base material that is to be lacquered. Curing the applied sap requires "drying" it in a warm, humid chamber or closet for 12 to 24 hours where the urushiolpolymerizes to form a clear, hard, and waterproof surface. In its liquid state, urushiol can cause extreme rashes, even from vapours. Once hardened, reactions are possible but less common.[citation needed]
Products coated withlacquer are recognizable by an extremely durable and glossy finish. Lacquer has many uses; some common applications includetableware,musical instruments,fountain pens,[6]jewelry, andbows for archery. There are various types oflacquerware. Thecinnabar-red is highly regarded. Unpigmented lacquer is dark brown but the most common colors of urushiol finishes are black and red, from powderediron oxide pigments of ferrous-ferric oxide (magnetite) andferric oxide (rust), respectively. Lacquer is painted on with a brush and is cured in a warm andhumid environment.[citation needed]
The leaves, seeds, and theresin of the Chinese lacquer tree are sometimes used inChinese medicine for the treatment of internal parasites and for stopping bleeding. Compoundsbutein andsulfuretin areantioxidants, and have inhibitory effects onaldose reductase andadvanced glycation processes.[7]
Buddhist monks who practiced the art ofSokushinbutsu would use the tree's sap in their ceremony.[citation needed]
The fruits ofT. vernicifluum can also be processed to produce a waxy substance known asJapan wax used for numerous purposes including varnishing furniture and producing candles.[8][9] The fruits of the trees are harvested, dried, steamed, and pressed to extract the wax, which hardens when cooled.[10]
