Urushi lacquer at home: telling real urushi from synthetic, and how to care for it

What urushi is

Japan's Forestry Agency describes urushi as a refined mixture of sap and resin collected from the urushi tree, used for centuries to coat tableware, crafts and buildings and as an adhesive.

Most urushi used in Japan today is not produced in Japan. In its annual report on forests and forestry for fiscal 2024, the Agency records domestic consumption of 29.8 tonnes in 2023 and domestic production of 1.7 tonnes, equal to 5.5% of consumption. Production has risen since 2015, after the Agency for Cultural Affairs decided in fiscal 2014 to use domestic urushi in principle for repairing National Treasure and Important Cultural Property buildings. If the origin of the lacquer matters to you, ask the maker directly; where a piece was made and where its urushi came from can differ.

Reading the label

For wooden and plastic tableware and kitchen items coated with urushi or cashew resin, the Consumer Affairs Agency's guidance under the Household Goods Quality Labeling Act sets out what the label must show. The product name 漆器 (shikki) may be used only when every coated surface uses natural urushi alone. Items coated with cashew or synthetic resin use a name such as 合成漆器 (gosei shikki, synthetic lacquerware), and an item that mixes urushi with synthetic coatings cannot be called 漆器.

The label also states the surface coating and the base material. These are the terms to look for:

• 漆塗装 (urushi toso): urushi coating
• ウレタン塗装 (uretan toso): urethane resin coating
• カシュー塗装 (kashu toso): cashew resin coating
• メラミンアルキド塗装 and ユリアアルキド塗装: melamine alkyd and urea alkyd resin coatings
• 天然木 (tennen-moku): natural wood base, sometimes with the species in brackets
• 木粉 (mokufun): wood flour mixed with resin, with its percentage by weight

Furniture and larger pieces

Where more than one coating is used, the guidance requires each coated part to be named, and an undercoat may be shown in brackets as 下地塗装 (shitaji toso). Very small items, under 200 square centimetres seen from above in normal use, may show only the coating and the base material.

The labelling rule covers tableware and kitchen items. A lacquered dining table, a tray stand or a chest of drawers falls outside it, so ask the maker or shop in writing which coating is on each surface, whether there is a synthetic undercoat, what the base wood is, and whether they can repair or recoat the piece later. Keep the answer with the receipt.

Choosing urushi for a home you visit a few times a year

Synthetic coatings have their place. A urethane-coated tray can be a sensible choice for a busy kitchen, as long as you know what you are buying. Check that the label, the price and what the shop tells you all agree.

For pieces that will live in a Tokyo apartment you leave closed for weeks at a time, a few questions at the counter save trouble later.

• Is the name on the label 漆器 or 合成漆器, and what coating and base does it list
• Is the base solid wood, and which species
• Which care steps does the maker recommend, and are they printed on the tag
• Can the maker or shop repair or recoat it, and how do you contact them from abroad
• Can the shop pack and ship it to your Tokyo address

Using and washing urushi every day

Urushi is made to be used. The care points below follow the examples the Consumer Affairs Agency gives for lacquerware labels.

In practice, wipe each piece dry soon after washing, and avoid stacking lacquer with ceramics or metal, which can scratch the surface.

• Wash in warm or plain water after use and wipe with a soft cloth
• Do not scrub with scouring pads or polishing powder
• Do not leave strongly acidic foods such as vinegar or lemon in the piece; the surface can change and lose its gloss
• Do not put it in a microwave
• Do not wash it in a dishwasher

Light, storage and the apartment you leave empty

The Agency's guidance also lists keeping lacquerware out of direct sunlight, which can cause discoloration or deformation. In a Tokyo apartment this means no lacquer on a sunny windowsill or a shelf that catches afternoon light, and none in front of an air conditioner outlet or heater.

Before you leave for a long stretch, make sure every piece is completely dry, wrap it in soft cloth or paper, and store it in a closed cupboard away from the windows. On your next visit, unwrap the pieces, check them in daylight and use them. If the apartment tends to be damp while it is closed, look after the humidity of the room as a whole; our article on humidity in an empty apartment covers the steps.

Chips, wear and repair

Urushi can be repaired and recoated by a lacquer craftsperson. A worn rim, a chip or a dull patch is usually a question for the maker or the shop that sold the piece; production areas such as Wajima in Ishikawa have cooperatives of makers and dealers.

Do not try to fill or polish damage with household products. Note when and how the damage happened, take clear photographs, and send them to the maker with the original label or receipt.