Lacquer. A non-resinous sap taken from Rhus verniciflua, a tree which grows in East Asian countries. Lacquer's most distinct physical characteristic is that it will only dry in a moist atmosphere and at a moderate temperature. Once dry, it undergoes no further change except that with time its transparent color becomes deeper.
Lacquer is more durable than synthetic equivalents, and wooden utensils coated with lacquer are strengthened against heat and humidity. In Japan urushi has been used as a varnish since the late Jōmon period. It is also used as an adhesive, sometimes as a structural material, and also as electrical insulation. By adding an iron-based pigment to transparent lacquer suki-urushi 透漆, colored lacquer iro-urushi 色漆 of various hues becomes possible. For the production of lacquerware, see *urushi-nuri 漆塗.