Grades & Types of Urushi
Urushi is sold under a confusing number of names because it's classified along two independent axes at once: how refined it is, and how much oil has been blended in. Getting the vocabulary straight will save you from buying the wrong grade for the layer you're working on. (Tamenuri Studio, Types of urushi; Suzanne Ross, Urushi FAQs)
Raw lacquer (ki-urushi)
Crude sap that has only been filtered to remove bark and solids. Sold in grades depending on harvest timing and intended use:
| Grade | Typical use | Notes |
|---|---|---|
| Ki-urushi / Seshime | Base coats, putties (kokuso/sabi), intermediate layers, first practice coats | The cheap "workhorse" grade — start here. Autumn-harvest sap tends to be lower quality and is reserved for undercoats. (Tamenuri) |
| Kijōmi | Wiping coats, higher-end topwork | Marketed specifically for finishing/wiping applications. |
| Naka-nuri urushi | Middle coats | Summer-harvested, hand-stirred in vats to reduce water content and thicken it. (Suzanne Ross) |
Refined clear lacquer
Made by nayashi (mechanically stirring/homogenizing the sap into a uniform fine emulsion) and kurome (slow heating to reduce water content). This is where the well-known top-layer names come from:
| Name | Oil? | Typical use |
|---|---|---|
| Sugurome / Roiro clear | No oil | Backbone lacquer for roiro polishing workflows (see Chapter 20) |
| Kijiro | No oil | Clear, refined; tuned to show the wood grain through — the base of the tamenuri finish |
| Shu-ai | Oil-added | Nuri-tate / hana-nuri style finishing — glossy straight off the brush, no polishing pass |
| Nashiji | Oil-added, tinted with gamboge | Warm yellow ground for the nashiji sprinkled-gold effect (Chapter 28) |
| Hakushita | — | Formulated specifically for foil/leaf adhesion (gold, silver, tin) |
Black urushi (kuro-urushi)
Made by stirring iron compounds into refined lacquer during processing, which reacts with the tannins to produce a deep black. Available as a no-oil version for roiro polishing and an oil-added version for nuri-tate style work straight off the brush. (Tamenuri Studio)
Pigmented / colored urushi
Pigment dispersed into clear or lightly tinted urushi. Two hard rules recur across every source consulted: keep total pigment load under roughly 40% by weight (more weakens the cured film), and always filter pigmented urushi through fine yoshino-gami paper before use to strain out clumps and debris. (Tamenuri Studio) Not every pigment is chemically compatible with urushi — verify compatibility before committing a batch. (background)