Yoshikane White 2 KU Nashiji Stainless Clad Bunka 165mm Ebony by Hatsukokoro

The bunka knife (文化包丁) takes its name from bunka, culture. A Sakai knife maker ties the name to Japan's modernisation, when Western culture and Japanese tradition merged, and says it stands for that new era and for the knife's wide range of uses.

The same maker says that as diets broadened to meat, fish and vegetables, an all-purpose knife was wanted, and the bunka took features from both Japanese and Western knives.

The tip. One Japanese knife maker describes the bunka (文化包丁, kengata) as combining the good points of the gyuto and the nakiri with the tip cut at an angle, and the santoku as coming after it, by rounding that tip.

Both are all-purpose knives for the home; santoku (三徳) means three virtues, for the three foods it cuts: meat, fish and vegetables.

Shirogami 1 (White 1) has more carbon than Shirogami 2 (White 2): Proterial lists 1.25 to 1.35% carbon for Shirogami 1 and 1.05 to 1.15% for Shirogami 2, with the same silicon (0.10 to 0.20%) and manganese (0.20 to 0.30%) ranges for both.

Proterial describes both as carbon steel with minimum impurities, Shirogami 1 with the highest hardness and Shirogami 2 with high hardness, and gives a hardening hardness of over 60 HRC for both. It lists Shirogami 1 for the highest quality tipped tools, planes, chisels and razors, and Shirogami 2 for high quality tipped tools, chisels, razors, sickles, axes and gravers.

White 1, White 2 and White 3 are Proterial's Shirogami 1, Shirogami 2 and Shirogami 3. Proterial lists carbon at 1.25 to 1.35% for Shirogami 1, 1.05 to 1.15% for Shirogami 2 and 0.80 to 0.90% for Shirogami 3, with the same silicon and manganese ranges for all three and no chromium listed.

Proterial describes all three as carbon steel with minimum impurities, at highest, high and middle hardness in that order, and gives a hardening hardness of over 60 HRC for each.

Proterial lists 1.05 to 1.15% carbon for both steels; its Blue 2 table lists 0.20 to 0.50% chromium and 1.00 to 1.50% tungsten, while its White 2 table lists neither.

Proterial describes White 2 as a carbon steel with minimum impurities and high hardness, and Blue 2 as an alloy steel with tungsten and chromium to improve heat-treatment properties and wear resistance, with a hardening hardness of over 60 HRC for both. In its Japanese materials, Proterial calls its Aogami (青紙) steels high-carbon steel (高炭素鋼). Neither steel is close to the JSSA's 10.5% minimum for stainless.

Yoshikane's own company page dates the founding to Taisho 8, 1919, when the founder, whose name the company writes as 吉田金吉, started the business in Shimotajima, Sanjo.

The same page records a fourth-generation succession in 2013, naming the successor as 山本和臣, and the company's incorporation as 株式会社吉金刃物 in 2022.

Both forms are correct, for two different things: the company writes its own name 吉金刃物, as the maker's site shows.

That page also records 吉兼 and 吉兼久 as the workshop's own brands, added in 1922.