Urushi has 2 uses, i.e., as an adhesive and as a paint Urushi.
Urushi ware is completed using both characteristics.
The raw unprocessed Urushi works mainly as a glue, and the refined Urushi works as a paint.
Urushi may not dry evenly when convection is used or direct heat from the sun. This is a common problematic characteristic. Traditionally the best method to dry the objects after painting with Urushi is to put them in a wet wooden box and to seal the box.
This method allows the Urushi to dry through the evaporative effect of the moisture inside of the box.
In other words, the Urushi hardens by the humidity.
Urushi craftsmen use large moistened cupboards as well as moistened wooden boxes. Regardless the size of box, it is referred to as a “bath”.
Urushi is not affected by alkali or acid once completely dried. As a result the Urushi is tough and does not deteriorate. Furthermore the Urushi is non conductive with excellent heat and electricity insulation.
Because of this property, for example, a thin Urushi ware soup bowl can be held by hands, even after pouring hot soup.