Uwa-nuri and nuritate: the final coat

Uwa-nuri is the upper or final coating stage in a built lacquer finish. Nuritate is one way to finish that coat: let it harden and leave its surface unpolished. The brushwork, film thickness, dust control, and curing orientation therefore remain visible in the finished object.

Keep the terms separate

The Japan Kogei Association distinguishes the two principal finish routes clearly: nuritate leaves the final coat as applied, while roiro continues through levelling, abrasive polishing, suri-urushi, and further polishing. A nuritate surface is not an unfinished roiro surface. It is a deliberate finish whose subdued, moist-looking lustre depends on a clean final application.

Choose lacquer for the intended finish

Start with the supplier's intended use, not the product name alone. Grade names vary among processors. Tamenuri Studio's practitioner guide groups clear oil-added refined lacquers such as shuai, and oil-added black topcoat lacquers, with nuri-tate or hana-nuri finishing. The added drying oil changes flow, gloss, and curing behaviour. Roiro work more commonly uses a no-oil refined topcoat that will tolerate the later polishing sequence. (Tamenuri Studio, Types of urushi)

• For nuritate: buy a refined topcoat explicitly sold for nuri-tate, hana-nuri, or an equivalent unpolished brush finish. Use black or a compatible coloured lacquer according to the design.
• For roiro: use the topcoat specified for the polishing system rather than assuming that a glossy oil-added lacquer will behave the same way.
• For colour: use premixed colour lacquer or pigments known to be compatible with urushi. The lacquer's own brown tone, the pigment, coat thickness, and curing conditions all affect the cured colour.

A Wajima topcoat specialist interviewed by the Japan Artisan Foundation explains why there is no dependable universal mixing ratio: lacquer behaviour changes with origin, harvest, season, temperature, and humidity. Keep a labelled sample from the batch and coat a prepared test piece before committing the object. Record the lacquer, any additive, the substrate, application date, temperature, and relative humidity.

Prepare before opening the container

The top coat cannot hide poor preparation. The preceding middle coat should be hard enough to level without smearing, flat through the field and edges, and free of exposed ground or deep scratches. In the documented Wajima sequence, final preparation includes careful wet sanding to remove dust and oils before top coating. (Wajima Museum of Urushi Art, A30–A31)

1. Finish all shaping and levelling. Correct hollows, ridges, pinholes, and edge damage in the appropriate earlier layer. A wet top coat is not filler.
2. Clean the room first. Stop dusty work, wipe the bench and furo, and allow disturbed dust to settle. Put on clean workwear that has not been used for sanding.
3. Prepare supports and orientation. Decide how the object will be held, where the wet edges stop, and whether inside and outside will be coated separately. Make sure the piece can enter the furo without touching a wet face.
4. Prepare the complete tool set. Set out the finishing brush, spatula, filter, lacquer tray, dust brush, non-metal picking tool, light, timer, and control swatch. Do not search for tools while the coat is setting.
5. Inspect in raking light. Remove sanding slurry, fingerprints, loose fibres, and particles without contaminating the prepared surface with oil from bare skin.

Filter, test, and load the brush

The Japan Artisan Foundation describes high-purity lacquer that has been filtered repeatedly for uwa-nuri. Filtering removes bark, fibres, and other solids; it does not fix dust already present on the object or in the room. Use a clean filter intended for urushi, clean tools, and a covered container. Do not add solvent simply because the lacquer feels difficult to brush. Any adjustment must follow the supplier's guidance and should first be tried on the control swatch.

Work a modest quantity into the finishing brush so the bristles are charged evenly rather than flooded at the tip. Test the loaded brush on a separate prepared surface. The stroke should release a continuous film without dry skips, heavy banks at the ends, or loose bristles. The professional Wajima process uses a dedicated human-hair finishing brush; the broader lesson is to reserve the cleanest, best-conditioned brush for the final coat and to keep it free of old particles and cleaning residue.

Apply an even coat, then stop

The documented Wajima sequence first distributes an appropriate amount of lacquer, then uses a finishing brush to bring the film to an even thickness without visible brush marks. The inside and outside of a vessel are coated separately. This is a useful sequence for hand work even when the object and brush differ:

1. Distribute. Place enough lacquer across the work so every area can be covered before the film begins to change.
2. Spread. Join the wet areas into one continuous film. Carry the brush into corners and around rims without leaving a reservoir.
3. Finish. With the brush evenly loaded and pressure reduced, make orderly final passes that remove banks and obvious tracks. On a flat panel, keep the last passes consistent. On a vessel, follow the form and watch the rim, foot, and changes in curvature.
4. Inspect once. Use raking light to find a dry skip, sag, heavy edge, hair, or speck. Correct only what can still be corrected cleanly.

Remove fresh dust without scratching

Fushi-age is the removal of a visible particle from the wet coat. The Japan Artisan Foundation documents a thin bamboo or feather-shaft tool and specifically warns against metal, which can scratch the surface. Approach the speck with a clean, non-scratching point, lift it with the least contact possible, and allow the surrounding wet film to close. Do not dig for a particle once the lacquer has begun to skin. A small cured nib is usually safer to correct later than a large wet scar.

Orient the object during cure

Move the object to a clean furo without passing it through a dusty area. Support it so that no wet face touches the rack and condensation cannot drip onto the film. Curved work may need its orientation changed while the lacquer is still mobile so gravity does not pull the coat into a sag.

In the Wajima workshop documented by the Japan Artisan Foundation, vessels go into a rotating bath and are flipped every five or six minutes during the early stage. That is a description of one professional system, not a universal timer. The useful principle is to plan rotation around the object's shape, the lacquer's flow, and the point at which the film stops moving. Keep a written rotation schedule for repeat work, and avoid opening the furo more often than necessary.

Do not force the cure with a single humidity number copied from another workshop. The same Wajima account notes that temperature and humidity strongly affect the result and that excessive humidity can make a particular topcoat set too quickly, shrink, show brush marks, and darken. Use the range supplied for your lacquer, measure conditions at the object, avoid condensation and abrupt changes, and compare the object with its control swatch. Chapter 21 gives the diagnostic sequence.

Know when the top coat is ready

A nuritate finish stops after the last coat has hardened. Do not polish out its characteristic surface and still call the result nuritate. If the design calls for roiro, continue with the levelled and polished sequence in Chapter 20.

Read faults before correcting them

For a nuritate object, a serious defect usually means allowing the coat to harden, levelling the fault without cutting through the surrounding surface, restoring any exposed colour layer, and applying another clean top coat. Test the repair sequence on a swatch. A local polished spot will not match an otherwise unpolished finish.

Watch the final-coat workflow

These workshop films show the scale of the brush, the order of application, the inspection for dust, and the controlled movement of a coated vessel. Treat them as demonstrations of particular workshops, not universal recipes.

The archive's timestamped uwa-nuri method assembles further application and polishing footage into source-linked steps. Use it alongside this chapter, especially if the top coat will continue into roiro rather than stop at nuritate.

Continue from here

• Roiro-nuri covers the separate levelled and polished route after the top coat.
• Curing and troubleshooting gives a measured diagnostic order for tack, wrinkles, haze, and other failures.
• Sanding and polishing explains readiness checks, edge protection, scratch removal, and abrasive systems.