The Alchemy of Urushi: From Living Sap to Luminous Lacquer

Before it was art, Urushi was sap.
A slow, milky secretion from the Japanese lacquer tree, Toxicodendron vernicifluum — a relative of poison ivy. Its touch, in raw form, can raise blisters. Its transformation, once cured, gives birth to one of the most enduring finishes on earth.

At Takamichi Beauty Room, we love Urushi not only for its deep glow but for what it teaches: beauty born from slowness, precision, and time.

From Tree to Drop

In early summer, artisans make fine incisions in the bark of the lacquer tree. The sap that seeps out — called raw Urushi (arami-urushi) — is carefully scraped and collected, a few drops at a time.
A single tree produces only a few hundred grams per season, and only after 10 to 15 years of growth. The process is deliberately gentle; to take too much would kill the tree.

Each harvest is a conversation between tree and craftsman — part ritual, part science.

The Poison and the Cure

Fresh lacquer sap contains urushiol, the same allergen found in poison ivy and sumac. In its liquid state, it’s highly reactive and can irritate the skin.
Artisans who handle Urushi wear gloves and work with care, knowing that beauty here comes with risk.

But as the lacquer cures, the chemistry changes: oxygen and moisture transform the urushiol through polymerization, turning the sticky sap into a hard, glassy, and non-toxic surface. Once cured, it becomes food-safe, waterproof, and nearly eternal — an object that can survive centuries of use.

Time as Ingredient

After filtering and refining, raw lacquer is often aged for several years before use — sometimes up to four — allowing moisture to settle and enzymes to stabilize.
This quiet resting period deepens its color and improves its flow, much like the aging of wine or miso.

When ready, artisans brush it in ultra-thin layers, curing each coat in a muro — a warm, humid chamber — where time, air, and humidity work together to harden the surface.
Each layer takes 12 to 24 hours to set, and a single piece may require dozens of layers before it reaches its signature glow.

The Light Within

Urushi is not just black; it’s depth.
Light penetrates the surface and reflects through multiple layers, creating a sense of inner illumination — a kind of “wet shine” impossible to imitate with synthetic varnish.

Even after centuries, the surface can be sanded and recoated. Urushi doesn’t merely endure; it regenerates.

A Dialogue Between Centuries

Our Isuke lacquer boxes, trays, and tea caddies are part of a lineage that stretches back 400 years in Kyoto. Each one carries the patience of generations — a continuity between hand, tree, and time.

Urushi reminds us that some things can’t be rushed.
They must be grown, collected, brushed, and polished until they hum quietly with life.

→ Explore our Isuke lacquer collection — living history, finished in shine.