Tojiro Zen Black Nakiri

The nakiri bōchō (菜切り包丁), “knife for cutting greens,” is a traditional Japanese vegetable knife best used for up-and-down chopping. Unlike the santoku and gyuto (chef’s knife), which have narrow tips intended for cutting meat, the nakiri has a square tip and broad blade that maximize chopping power along the full length of the knife. The straighter edge ensures full contact with the cutting board, helping to cut through tough vegetable skins that a rounded edge can miss, while the rounded corner facilitates rock-chopping. Like other Japanese knives, the nakiri has a thinner blade and more acute edge than European knives, so it can effortlessly make straight cuts and doesn’t break stiff vegetable slices.

The blade is made using the centuries-old san mai (“three-layer”) construction technique, in which a hardened steel core is forge welded to a jacket of softer, more flexible steel for strength. Nakiyo San Mai blades are forged with a core of VG-10 cobalt alloy steel, a high-carbon stainless steel developed in Japan. Hardened to a Rockwell hardness of 60, it accommodates a long-lasting, razor-sharp edge. The core is clad in 13 chrome stainless steel, which strengthens the blade and guards against corrosion.

Zen Black blades are additionally treated with a black oxide conversion finish, which anodizes a microscopic layer of metal on the surface to chemically stable magnetite (Fe₃O₄). Often used on medical implements, this treatment improves the steel’s resistance to saltwater and is popular on boats or in coastal areas.

The handle is crafted from lightweight chestnut wood, which provides a secure grip without upsetting the knife’s balance. The wood is fire-blackened, enhancing its durability and water resistance, and secured with a ferrule (collar) of polypropylene resin. Its D-shaped shinogi profile maximizes comfort and ease of control.

Wash your knife by hand with warm water, soap, and a soft sponge or dish towel. Avoid prolonged exposure to heat or moisture. Remember—there's no such thing as a dishwasher-safe knife!

To prevent edge chips, avoid impacts with hard surfaces. Don't chop bones, shells, or frozen food, and cut only on a wood or bamboo cutting board. Don't leave your knife where the edge might come in contact with something hard, such as in a sink or a drawer with other knives.

Store your knife so that the edge is protected from abrasion and impact. We recommend a magnetic stand, but you can also use a knife block with horizontal slots. If you must keep it in a drawer, use an edge protector. See our storage options here.

Sharpen on a whetstone at an angle of 15° per side and finish at a grit of at least 1000, but preferably 3000 or higher. Pull-through and electric sharpeners should be avoided for Japanese knives.

Alternatively, you can have your knives sharpened professionally. Seattle Cutlery offers a state-of-the-art, mail-in sharpening service for our own customers, but other services may be available to you locally.

Honing steels are not necessary to maintain Japanese knives. You can optionally touch up the edge with a high-grit sharpening stone or a ceramic sharpening rod.

All Nakiyo, Tojiro, Sabatier, and SeaCut products sold by Seattle Cutlery are covered by our lifetime warranty against defects in materials and workmanship. If you follow our care and maintenance advice and your knife ever fails during honest use, we will gladly repair or replace it. Our warranty does not cover regular wear and tear or damage due to misuse, but we may still be able to help in some cases.